diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index 40fd8399f..a8aea2005 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -4,7 +4,7 @@
 
 Note that bug reports and feature requests for related projects should be filed in the corresponding repositories for [i3status](https://github.com/i3/i3status) and [i3lock](https://github.com/i3/i3lock).
 
-## i3 bug reports and feature requests
+## i3 bug reports
 
 1. Read the [debugging instructions](https://i3wm.org/docs/debugging.html).
 2. Make sure you include a link to your logfile in your report (section 3).
@@ -18,6 +18,20 @@ Note that bug reports and feature requests for related projects should be filed
    encountered the issue you are about to report while using a compositor,
    please try reproducing it without a compositor.
 
+## i3 feature requests
+
+1. Read the [project goals](https://i3wm.org) on the website and make sure that
+   they are compatible with the feature you want to suggest.
+2. We are generally happy with the current feature set of i3 and instead focus
+   on maintenance such as stability and fixing bugs. New features will rarely
+   be considered if they require additional configuration and/or commands, or
+   if they add significant complexity (either through the exposed configuration
+   or mental complexity) to the project.
+3. Explain in detail what problem the feature addresses and why existing
+   features fall short.
+4. Consider whether the feature could instead be implemented using the
+   [IPC](https://i3wm.org/docs/ipc.html) or other external tooling.
+
 ## Pull requests
 
 * Before sending a pull request for new features, please check with us that the
diff --git a/.github/ISSUE_TEMPLATE.md b/.github/ISSUE_TEMPLATE.md
index 726b40079..857c1defd 100644
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -6,7 +6,12 @@ IMPORTANT NOTE: If your issue is not specific to any feature provided by i3-gaps
 -->
 
 ## I'm submitting a…
-<!-- Please check one of the following options with "x" -->
+<!-- 
+Check one of the following options with "x".
+
+Please note that at this point we focus on maintaining i3 and fixing bugs, and will rarely consider features which require further configuration or significant complexity.
+In such cases you should consider and present specific benefits derived from adding this feature such that it can be weighed against the cost of additional complexity and maintenance.
+-->
 <pre>
 [ ] Bug
 [ ] Feature Request
diff --git a/.github/ISSUE_TEMPLATE/config.yml b/.github/ISSUE_TEMPLATE/config.yml
new file mode 100644
index 000000000..02251489a
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/config.yml
@@ -0,0 +1,4 @@
+contact_links:
+  - name: Ask a question or request support for using i3
+    url: https://github.com/i3/i3/discussions/new
+    about: Ask a question or request support for using i3
diff --git a/.github/ISSUE_TEMPLATE/feature_request.md b/.github/ISSUE_TEMPLATE/feature_request.md
index e1c169a58..c41d1cac3 100644
--- a/.github/ISSUE_TEMPLATE/feature_request.md
+++ b/.github/ISSUE_TEMPLATE/feature_request.md
@@ -8,7 +8,7 @@ PLEASE HELP US PROCESS GITHUB ISSUES FASTER BY PROVIDING THE FOLLOWING INFORMATI
 -->
 
 ## I'm submitting a…
-<!-- Please check one of the following options with "x" -->
+<!-- Check one of the following options with "x" -->
 <pre>
 [ ] Bug
 [x] Feature Request
@@ -28,6 +28,15 @@ Describe the desired behavior you expect after mitigation of the issue,
 e.g., »The window left next to the current window should be focused.«
 -->
 
+## Impact
+<!--
+Please note that at this point we focus on maintaining i3 and fixing bugs, and will rarely consider features which require further configuration or significant complexity.
+In such cases you should consider and present specific benefits derived from adding this feature such that it can be weighed against the cost of additional complexity and maintenance.
+-->
+<pre>
+[ ] This feature requires new configuration and/or commands
+</pre>
+
 ## Environment
 <!--
 Please include your exact i3 version.
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
new file mode 100644
index 000000000..34bd45806
--- /dev/null
+++ b/.github/workflows/main.yml
@@ -0,0 +1,94 @@
+name: GitHub Actions
+
+on:
+  push:
+    branches: [ gaps-next, gaps, actions ]
+  pull_request:
+    branches: [ gaps-next ]
+
+jobs:
+  build:
+    name: build and test
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        compiler: [gcc, clang]
+    env:
+      CC: ${{ matrix.compiler }}
+      DOCKER_PASS: ${{ secrets.DOCKER_PASS }}
+      DOCKER_EMAIL: ${{ secrets.DOCKER_EMAIL }}
+      DOCKER_USER: ${{ secrets.DOCKER_USER }}
+      GH_TOKEN: ${{ secrets.GH_TOKEN }}
+      BALTO_TOKEN: ${{ secrets.BALTO_TOKEN }}
+
+    steps:
+    - uses: actions/checkout@v2
+    - run: git fetch --prune --unshallow
+    - name: construct container name
+      run: |
+        echo "BASENAME=i3wm/travis-base:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base.Dockerfile)" >> $GITHUB_ENV
+        echo "BASENAME_386=i3wm/travis-base-386:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base-386.Dockerfile)" >> $GITHUB_ENV
+        echo "BASENAME_UBUNTU=i3wm/travis-base-ubuntu:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base-ubuntu.Dockerfile)" >> $GITHUB_ENV
+        echo "BASENAME_UBUNTU_386=i3wm/travis-base-ubuntu-386:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base-ubuntu-386.Dockerfile)" >> $GITHUB_ENV
+    - name: fetch or build Docker container
+      run: |
+        docker pull ${{ env.BASENAME }} || ./travis/docker-build-and-push.sh ${{ env.BASENAME }} travis/travis-base.Dockerfile
+    - name: fetch or build extra Docker containers
+      run: |
+        echo "::group::Ubuntu amd64"
+        ./travis/skip-pkg.sh || docker pull ${{ env.BASENAME_UBUNTU }} || ./travis/docker-build-and-push.sh ${{ env.BASENAME_UBUNTU }} travis/travis-base-ubuntu.Dockerfile
+        echo "::endgroup::"
+        echo "::group::Debian i386"
+        ./travis/skip-pkg.sh || docker pull ${{ env.BASENAME_386 }} || ./travis/docker-build-and-push.sh ${{ env.BASENAME_386 }} travis/travis-base-386.Dockerfile
+        echo "::endgroup::"
+        echo "::group::Ubuntu i386"
+        ./travis/skip-pkg.sh || docker pull ${{ env.BASENAME_UBUNTU_386 }} || ./travis/docker-build-and-push.sh ${{ env.BASENAME_UBUNTU_386 }} travis/travis-base-ubuntu-386.Dockerfile
+        echo "::endgroup::"
+    - name: verify safe wrapper functions are used
+      run: |
+        docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME }} ./travis/check-safe-wrappers.sh
+    - name: verify code formatting
+      run: |
+        docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME }} ./travis/check-formatting.sh
+    - name: build i3
+      run: |
+        docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 -e CC ${{ env.BASENAME }} /bin/sh -c 'rm -rf build; mkdir -p build && cd build && CFLAGS="-Wformat -Wformat-security -Wextra -Wno-unused-parameter -Wstrict-prototypes -Wmissing-prototypes -Werror -fno-common" meson .. -Ddocs=true -Dmans=true -Db_sanitize=address && ninja -v'
+    - name: check spelling
+      run: |
+        docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME }} ./travis/check-spelling.pl
+    - name: run i3 tests
+      run: |
+        docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 -e CC ${{ env.BASENAME }} ./travis/run-tests.sh
+    - name: Archive test logs
+      uses: actions/upload-artifact@v2
+      with:
+        name: test-logs
+        path: build/testsuite-*
+      if: ${{ failure() }}
+    - name: build dist tarball
+      run: |
+        docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 -e CC ${{ env.BASENAME }} /bin/sh -c 'rm -rf distbuild; mkdir distbuild && cd distbuild && meson .. -Ddocs=true -Dmans=true && ninja -v dist'
+    - name: build Debian packages
+      run: |
+        echo "::group::Debian amd64"
+        ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME }} ./travis/debian-build.sh deb/debian-amd64/DIST
+        echo "::endgroup::"
+        echo "::group::Ubuntu amd64"
+        ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME_UBUNTU }} ./travis/debian-build.sh deb/ubuntu-amd64/DIST
+        echo "::endgroup::"
+        echo "::group::Debian i386"
+        ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME_386 }} linux32 ./travis/debian-build.sh deb/debian-i386/DIST
+        echo "::endgroup::"
+        echo "::group::Ubuntu i386"
+        ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME_UBUNTU_386 }} linux32 ./travis/debian-build.sh deb/ubuntu-i386/DIST
+        echo "::endgroup::"
+    - name: push Debian packages to balto
+      run: |
+        ./travis/skip-pkg.sh || travis/push-balto.sh
+    - name: build docs
+      run: |
+        ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${{ env.BASENAME }} ./travis/docs.sh
+    - name: push docs to GitHub pages
+      run: |
+        ./travis/skip-pkg.sh || travis/deploy-github-pages.sh
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 9935cb631..000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,71 +0,0 @@
-dist: trusty
-services:
-  - docker
-language: c
-compiler:
-  - gcc
-  - clang
-addons:
-  apt:
-    packages:
-    # For https support in HTTP::Tiny.
-    - libio-socket-ssl-perl
-env:
-  global:
-  - BASENAME="i3wm/travis-base:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base.Dockerfile)"
-  - BASENAME_386="i3wm/travis-base-386:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base-386.Dockerfile)"
-  - BASENAME_UBUNTU="i3wm/travis-base-ubuntu:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base-ubuntu.Dockerfile)"
-  - BASENAME_UBUNTU_386="i3wm/travis-base-ubuntu-386:$(date +'%Y-%m')-$(./travis/ha.sh travis/travis-base-ubuntu-386.Dockerfile)"
-  - secure: "B5IICA8MPx/FKaB50rTPqL8P1NU+Q0yuWl+lElL4+a9xSyLikfm3NzUPHoVwx8lNw2AVK6br7p0OmF7vMFjqAgrgc1cajTtEae5uFRKNUrWLpXM046YgNEYLLIHsQOjInxE+S4O6EFVzsUqsu8aeo2Xhq4sm4iUocG7e5isYgYo=" # DOCKER_PASS
-  - secure: "EIvrq8PG7lRjidppG0RCv4F0X4GP3DT9F5+ixVuGPfhK/hZT3jYC2AVY9G+NnUcXVwQEpW92rlqpftQ/qZ13FoyWokC8ZyoyD06fr5FPCfoFF3OczZwAJzZYkObI/hE9+/hXcylx/Os6N4INd2My1ntGk3JPsWL9riopod5EjSg=" # DOCKER_EMAIL
-  - secure: "hvhBunS4xXTgnIOsk/BPT7I7FrJhvVwCSt5PfxxvMqNaztOJI9BuK7ZrZ5Cy38KyHwlh3VHAH5AaCygJcPauoSQCV3bpnlbaWn3ruq2F0Q697Q5uNf73liXzyUqb9/Zvfvge4y4WWOhP5tVz1C6ZBe/NfhU7pqKLMA+6ads+99c=" # DOCKER_USER
-  - secure: "uJuuefmnJUuEH15ZD8xQilibx7EeBvMHBLoIZ8bgGHeleEImBD0XbD1ypvhYJKpviOmw5BkZmc9bVO8DGDEHYbSlIa2xDlF6vGrwgCEaxcMIhOAhv+dW9C/maJVieLOEPM01/fK2qdKESZaLvlopkWmxZwDyMObI9L7AMW9zQD8=" # BINTRAY_USER
-  - secure: "L3aPSNLySPXtWCW+xf8h/AAdquwNgxyTQpYOwexJmTPav82Qx8uQlp1yJkUmt+a+FLZDFfQeMivaHq0311RvuQVmkAJx49DjaddrwqOJut2UPsoVDn1WeuAcSHIXOq/0H+zgFMr/PGY0HXIsw1mTMhgheGJNqg09BvYWROCEAcA=" # BINTRAY_KEY
-  - secure: "sBMVn4C/WRWgoAytEFGx4CC5O55Q63h02AcuBnb1jXcBm0RenoBpzUPtxSseJwDPUA1o/UkuEDDjm3PosT5NF+dvED01VDFMsPVE11K0u6+avYy3jYXqyUEDW3G2o6Wo/2aqNjmd++8jskBdS9+Cx9gaFbgxfzSp0Yfu3oJm/4c=" # GH_TOKEN
-install:
-  - if [ -a .git/shallow ]; then git fetch --unshallow; fi
-  - docker pull ${BASENAME} || ./travis/docker-build-and-push.sh ${BASENAME} travis/travis-base.Dockerfile
-  - ./travis/skip-pkg.sh || docker pull ${BASENAME_UBUNTU} || ./travis/docker-build-and-push.sh ${BASENAME_UBUNTU} travis/travis-base-ubuntu.Dockerfile
-  - ./travis/skip-pkg.sh || docker pull ${BASENAME_386} || ./travis/docker-build-and-push.sh ${BASENAME_386} travis/travis-base-386.Dockerfile
-  - ./travis/skip-pkg.sh || docker pull ${BASENAME_UBUNTU_386} || ./travis/docker-build-and-push.sh ${BASENAME_UBUNTU_386} travis/travis-base-ubuntu-386.Dockerfile
-script:
-  - docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME} ./travis/check-safe-wrappers.sh
-  - docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME} ./travis/check-formatting.sh
-  - docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 -e CC ${BASENAME} /bin/sh -c 'rm -rf build; mkdir -p build && cd build && CFLAGS="-Wformat -Wformat-security -Wextra -Wno-unused-parameter -Wstrict-prototypes -Wmissing-prototypes -Werror -fno-common" meson .. -Ddocs=true -Dmans=true -Db_sanitize=address && ninja -v'
-  - docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME} ./travis/check-spelling.pl
-  - docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 -e CC ${BASENAME} ./travis/run-tests.sh
-  - docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 -e CC ${BASENAME} /bin/sh -c 'rm -rf distbuild; mkdir distbuild && cd distbuild && meson .. -Ddocs=true -Dmans=true && ninja -v dist'
-  - ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME} ./travis/debian-build.sh deb/debian-amd64/DIST
-  - ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME_UBUNTU} ./travis/debian-build.sh deb/ubuntu-amd64/DIST
-  - ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME_386} linux32 ./travis/debian-build.sh deb/debian-i386/DIST
-  - ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME_UBUNTU_386} linux32 ./travis/debian-build.sh deb/ubuntu-i386/DIST
-  - ./travis/skip-pkg.sh || docker run -v $PWD:/usr/src/i3/ -w /usr/src/i3 ${BASENAME} ./travis/docs.sh
-  - ./travis/skip-pkg.sh || travis/prep-bintray.sh
-
-deploy:
-  - provider: bintray
-    file: travis/bintray-autobuild-debian.json
-    user: $BINTRAY_USER
-    key: $BINTRAY_KEY
-    skip_cleanup: true
-    on:
-      branch: next
-      condition: $CC = gcc
-  - provider: bintray
-    file: travis/bintray-autobuild-ubuntu.json
-    user: $BINTRAY_USER
-    key: $BINTRAY_KEY
-    skip_cleanup: true
-    on:
-      branch: next
-      condition: $CC = gcc
-  - provider: script
-    script: travis/deploy-github-pages.sh
-    skip_cleanup: true
-    on:
-      branch: next
-      condition: $CC = gcc
-
-after_deploy:
-  - travis/cleanup-bintray.pl i3-autobuild
-  - travis/cleanup-bintray.pl i3-autobuild-ubuntu
diff --git a/README.gaps.md b/README.gaps.md
index d94d62c6f..a4702955b 100644
--- a/README.gaps.md
+++ b/README.gaps.md
@@ -1,4 +1,4 @@
-[![Travis](https://img.shields.io/travis/Airblader/i3.svg)](https://travis-ci.org/Airblader/i3)
+[![Build Status](https://github.com/Airblader/i3/actions/workflows/main.yml/badge.svg)](https://github.com/Airblader/i3/actions/workflows/main.yml)
 [![Issues](https://img.shields.io/github/issues/Airblader/i3.svg)](https://github.com/Airblader/i3/issues)
 [![Forks](https://img.shields.io/github/forks/Airblader/i3.svg)](https://github.com/Airblader/i3/network)
 [![Stars](https://img.shields.io/github/stars/Airblader/i3.svg)](https://github.com/Airblader/i3/stargazers)
@@ -19,7 +19,7 @@ Please refer to the [wiki](https://github.com/Airblader/i3/wiki/installation).
 
 For bug reports or feature requests regarding i3-gaps specifically, open an issue on [GitHub](https://www.github.com/Airblader/i3). If your issue is with core i3 functionality, please report it [upstream](https://www.github.com/i3/i3).
 
-For support & all other kinds of questions, you can ask your question on the official [subreddit /r/i3wm](https://www.reddit.com/r/i3wm).
+For support & all other kinds of questions, you can ask your question on [GitHub Discussions](https://github.com/i3/i3/discussions).
 
 # Features
 
diff --git a/RELEASE-NOTES-4.19.1 b/RELEASE-NOTES-4.19.1
deleted file mode 100644
index 72e479c78..000000000
--- a/RELEASE-NOTES-4.19.1
+++ /dev/null
@@ -1,27 +0,0 @@
-
- ┌──────────────────────────────┐
- │ Release notes for i3 v4.19.1 │
- └──────────────────────────────┘
-
-This is i3 v4.19. This version is considered stable. All users of i3 are
-strongly encouraged to upgrade.
-
-This is a bugfix release for v4.19
-
- ┌────────────────────────────┐
- │ Bugfixes                   │
- └────────────────────────────┘
-
-  • fix workspaces not moving to assigned output after output becomes available
-  • fix duplicate bindcode after i3-config-wizard
-  • fix commented-out rofi call in default i3 config
-
- ┌────────────────────────────┐
- │ Thanks!                    │
- └────────────────────────────┘
-
-Thanks for testing, bugfixes, discussions and everything I forgot go out to:
-
-  Anaël Beutot, Imran Virani, Orestis Floros
-
--- Michael Stapelberg, 2021-02-01
diff --git a/RELEASE-NOTES-4.20 b/RELEASE-NOTES-4.20
new file mode 100644
index 000000000..4345a56bd
--- /dev/null
+++ b/RELEASE-NOTES-4.20
@@ -0,0 +1,93 @@
+
+ ┌──────────────────────────────┐
+ │ Release notes for i3 v4.20   │
+ └──────────────────────────────┘
+
+This is i3 v4.20. This version is considered stable. All users of i3 are
+strongly encouraged to upgrade.
+
+Two long-awaited features have been added:
+
+ 1. You can now use an “include” directive in your i3 config:
+    https://i3wm.org/docs/userguide.html#include
+
+ 2. You can now enable showing window icons in window titlebars:
+    https://i3wm.org/docs/userguide.html#title_window_icon
+
+In case you notice any issues regarding your background/wallpaper, note:
+
+  Some login managers (e.g. gdm) start the X11 server with the -background none
+  flag. When this flag is set, a background needs to be explicitly set later in
+  the X11 session, otherwise stale copies of closed windows remain visible on
+  the X11 root window (symptom looks like “my terminal window is not closing”).
+
+  i3 works around this situation by setting a screenshot as background when
+  starting. Any background you set before starting i3 (e.g. in your Xsession) or
+  after starting i3 (e.g. via exec statements in the i3 config) will be visible.
+
+  A downside of this workaround is that if you have any windows already open in
+  your X11 session, those will be part of the screenshot.
+
+  To fix this issue, starting in v4.20, i3 detects whether the -background none
+  option is enabled and only then sets a screenshot as background.
+
+ ┌────────────────────────────┐
+ │ Changes in i3 v4.20        │
+ └────────────────────────────┘
+
+  • default config: use dex for XDG autostart
+  • docs/ipc: document scratchpad_state
+  • ipc: the GET_CONFIG request now returns all included files and their details
+  • i3-nagbar: position on focused monitor by default
+  • i3-nagbar: add option to position on primary monitor
+  • i3bar: use first bar config by default
+  • i3-dmenu-desktop: ignore duplicate files and directories (fixes crash on NixOS)
+  • i3-dump-log -f now uses UNIX sockets instead of pthreads. The UNIX socket approach
+    should be more reliable and also more portable.
+  • When clicking on a tab, focus its child (like when scrolling), or (if
+    already focused), focus the tab container (alternatingly).
+  • Implement the include config directive:
+    https://i3wm.org/docs/userguide.html#include
+  • Implement optionally showing window icons in titlebar:
+    https://i3wm.org/docs/userguide.html#title_window_icon
+  • Allow for_window to match against WM_CLIENT_MACHINE
+  • Add %machine placeholder (WM_CLIENT_MACHINE) to title_format
+  • 'move container|workspace to output': toggle a workspace (or container)
+    between multiple outputs when multiple output names specified.
+  • Add 'move container|workspace to output next'
+  • Add 'all' window matching criterion
+  • Acquire the WM_Sn selection when starting as required by ICCCM
+  • Add --replace command line argument to replace an existing WM
+  • Notify systemd when i3 is ready, allowing other services in a systemd user session
+    to use i3 as a dependency
+
+ ┌────────────────────────────┐
+ │ Bugfixes                   │
+ └────────────────────────────┘
+
+  • i3bar: properly close file descriptors
+  • i3bar: properly restart status command after config change
+  • i3bar: exit with 1 when a wrong command line argument is used
+  • ipc: return proper signed int for container positions: negative values were
+    returned as large 32 bits integers
+  • when initializing new outputs, avoid duplicating workspace numbers
+  • fix workspaces not moving to assigned output after output becomes available
+  • fix duplicate bindcode after i3-config-wizard
+  • fix commented-out rofi call in default i3 config
+  • clear pixmap before drawing to prevent visual garbage
+  • fix crash with "layout default"
+  • send an "output" event on XRandR 1.5 monitor configuration change
+
+ ┌────────────────────────────┐
+ │ Thanks!                    │
+ └────────────────────────────┘
+
+Thanks for testing, bugfixes, discussions and everything I forgot go out to:
+
+  ajakk, Albert Safin, Anaël Beutot, Antoine Martin, Dmitri Goutnik, ekarpp,
+  Imran Virani, Ingo Bürk, Isaac Garzon, Ivan Milov, Jay Khandkar, j-jzk, Ken
+  Gilmer, Kjetil Torgrim Homme, lbonn, Michael Stapelberg, Orestis Floros, Ralph
+  Gutkowski, Romuald Brunet, tomty89, Tristan Giles, Tudor Brindus, Uli
+  Schlachter, Vincent Bernat, Vladimir Panteleev
+
+-- Michael Stapelberg, 2021-10-19
diff --git a/debian/changelog b/debian/changelog
index c9df86768..3a6d59872 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,14 +1,20 @@
-i3-wm (4.19.1-1) unstable; urgency=medium
+i3-wm (4.20-1) unstable; urgency=medium
 
   * New upstream release.
 
- -- Michael Stapelberg <stapelberg@debian.org>  Mon, 19 Oct 2020 22:48:30 +0200
+ -- Michael Stapelberg <stapelberg@debian.org>  Tue, 19 Oct 2021 08:45:18 +0200
+
+i3-wm (4.19.2-1) unstable; urgency=medium
+
+  * New upstream release.
+
+ -- Michael Stapelberg <stapelberg@debian.org>  Sat, 27 Feb 2021 10:32:17 +0100
 
 i3-wm (4.19-1) unstable; urgency=medium
 
   * New upstream release.
 
- -- Michael Stapelberg <stapelberg@debian.org>  Sun, 15 Nov 2020 18:28:11 +0100
+ -- Michael Stapelberg <stapelberg@debian.org>  Mon, 19 Oct 2020 22:48:30 +0200
 
 i3-wm (4.18.3-1) unstable; urgency=medium
 
diff --git a/docs/hacking-howto b/docs/hacking-howto
index cc08cd1fb..01e5c7fde 100644
--- a/docs/hacking-howto
+++ b/docs/hacking-howto
@@ -400,8 +400,8 @@ the correct state.
 Then, it looks through all bindings and gets the one which matches the received
 event.
 
-The bound command is parsed by the cmdparse lexer/parser, see +parse_cmd+ in
-+src/cmdparse.y+.
+The bound command is parsed by the i3 parser, see +parse_command+ in
++src/commands_parser.c+.
 
 == Manage windows (src/main.c, manage_window() and reparent_window())
 
diff --git a/docs/i3-pod2html b/docs/i3-pod2html
index e2de51b36..80e98a4e9 100755
--- a/docs/i3-pod2html
+++ b/docs/i3-pod2html
@@ -83,7 +83,7 @@ $parser->html_header_after_title(
 			<ul id="nav">
 				<li><a style="border-bottom: 2px solid #fff" href="/docs">Docs</a></li>
 				<li><a href="/screenshots">Screens</a></li>
-				<li><a href="https://www.reddit.com/r/i3wm/">FAQ</a></li>
+				<li><a href="https://www.github.com/i3/i3/discussions">Get Help</a></li>
 				<li><a href="/contact">Contact</a></li>
 				<li><a href="https://bugs.i3wm.org/">Bugs</a></li>
 			</ul>
diff --git a/docs/i3-sync-working.dia b/docs/i3-sync-working.dia
index 9f1c3bc8c..258038289 100644
Binary files a/docs/i3-sync-working.dia and b/docs/i3-sync-working.dia differ
diff --git a/docs/i3-sync-working.png b/docs/i3-sync-working.png
index dce44ac5a..419334d0e 100644
Binary files a/docs/i3-sync-working.png and b/docs/i3-sync-working.png differ
diff --git a/docs/i3-sync.dia b/docs/i3-sync.dia
index 0945ae262..c8fb83594 100644
Binary files a/docs/i3-sync.dia and b/docs/i3-sync.dia differ
diff --git a/docs/i3-sync.png b/docs/i3-sync.png
index b64cce259..c9a5a01c8 100644
Binary files a/docs/i3-sync.png and b/docs/i3-sync.png differ
diff --git a/docs/i3bar-protocol b/docs/i3bar-protocol
index c1bf8f808..82c2f6ca8 100644
--- a/docs/i3bar-protocol
+++ b/docs/i3bar-protocol
@@ -191,7 +191,7 @@ separator_block_width::
 	is 9 pixels), since the separator line is drawn in the middle.
 markup::
 	A string that indicates how the text of the block should be parsed. Set to
-	+"pango"+ to use https://developer.gnome.org/pango/stable/pango-Markup.html[Pango markup].
+	+"pango"+ to use https://developer.gnome.org/pango/1.46/[Pango markup].
 	Set to +"none"+ to not use any markup (default). Pango markup only works
 	if you use a pango font.
 
diff --git a/docs/ipc b/docs/ipc
index bb8719cb4..02c6f9a96 100644
--- a/docs/ipc
+++ b/docs/ipc
@@ -14,7 +14,8 @@ most languages. In the default configuration file, the ipc-socket gets created
 in +/tmp/i3-%u.XXXXXX/ipc-socket.%p+ where +%u+ is your UNIX username, +%p+ is
 the PID of i3 and XXXXXX is a string of random characters from the portable
 filename character set (see mkdtemp(3)). You can get the socketpath from i3 by
-calling +i3 --get-socketpath+.
+executing +i3 --get-socketpath+, which will print the path to the standard
+output (plus a newline).
 
 All i3 utilities, like +i3-msg+ and +i3-input+ will read the +I3_SOCKET_PATH+
 X11 property, stored on the X11 root window.
@@ -39,12 +40,12 @@ my $sock = IO::Socket::UNIX->new(Peer => $path);
 
 == Sending messages to i3
 
-To send a message to i3, you have to format in the binary message format which
-i3 expects. This format specifies a magic string in the beginning to ensure
-the integrity of messages (to prevent follow-up errors). Following the magic
-string comes the length of the payload of the message as 32-bit integer, and
-the type of the message as 32-bit integer (the integers are not converted, so
-they are in native byte order).
+To send a message to i3, you have to format it in the binary message format
+which i3 expects. This format specifies a magic string in the beginning to
+ensure the integrity of messages (to prevent follow-up errors). Following the
+magic string comes the length of the payload of the message as a 32-bit
+integer, and the type of the message as a 32-bit integer (the integers are not
+converted, so they are in native byte order).
 
 The magic string currently is "i3-ipc" and will only be changed when a change
 in the IPC API is done which breaks compatibility (we hope that we don’t need
@@ -96,18 +97,30 @@ $sock->write(format_ipc_command("exit"));
 
 == Receiving replies from i3
 
-Replies from i3 usually consist of a simple string (the length of the string
-is the message_length, so you can consider them length-prefixed) which in turn
-contain the JSON serialization of a data structure. For example, the
-GET_WORKSPACES message returns an array of workspaces (each workspace is a map
-with certain attributes).
+Each message sent to i3 will cause exactly one reply to be sent in return. The
+order of the sent replies will always correspond to the order of the sent
+requests. The only exception to this is <<events>>, which (once subscribed to)
+may be sent at any time (though never in the middle of another event or reply).
 
-=== Reply format
+It is generally safe to send several messages to i3 without first waiting for a
+reply for each one (pipelining) -- though, note that depending on the language /
+network library you use, writing to the socket without also reading from it may
+cause a deadlock due to the socket buffers getting full.
 
 The reply format is identical to the normal message format. There also is
 the magic string, then the message length, then the message type and the
 payload.
 
+The payload of replies from i3 usually consists of a simple string (the length
+of the string is the message_length, so you can consider them length-prefixed),
+which in turn contain the JSON serialization of a data structure. For example,
+the GET_WORKSPACES message returns an array of workspaces (each workspace is a
+map with certain attributes).
+
+Replies currently have a 1:1 correspondence to messages, with the message type
+of the reply corresponding to the message type of the message which caused the
+reply to be sent.
+
 The following reply types are implemented:
 
 COMMAND (0)::
@@ -127,16 +140,30 @@ BAR_CONFIG (6)::
 VERSION (7)::
 	Reply to the GET_VERSION message.
 BINDING_MODES (8)::
-        Reply to the GET_BINDING_MODES message.
+	Reply to the GET_BINDING_MODES message.
 GET_CONFIG (9)::
 	Reply to the GET_CONFIG message.
 TICK (10)::
 	Reply to the SEND_TICK message.
+SYNC (11)::
+	Reply to the SYNC message.
 GET_BINDING_STATE (12)::
 	Reply to the GET_BINDING_STATE message.
 
+== Messages and replies
+
 [[_command_reply]]
-=== COMMAND reply
+=== RUN_COMMAND / COMMAND
+
+Run the payload as an https://i3wm.org/docs/userguide.html#list_of_commands[i3
+command] (like the commands you can bind to keys).
+
+*Message:*
+
+The message payload is the string containing the command to execute. There is
+no JSON encoding or trailing newline.
+
+*Reply:*
 
 The reply consists of a list of serialized maps for each command that was
 parsed. Each has the property +success (bool)+ and may also include a
@@ -170,7 +197,15 @@ When the specified command cannot be parsed, `success` will be false and
 -------------------
 
 [[_workspaces_reply]]
-=== WORKSPACES reply
+=== GET_WORKSPACES / WORKSPACES
+
+Get the list of current workspaces.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The reply consists of a serialized list of workspaces. Each workspace has the
 following properties:
@@ -234,7 +269,16 @@ output (string)::
 -------------------
 
 [[_subscribe_reply]]
-=== SUBSCRIBE reply
+=== SUBSCRIBE
+
+Subscribe this IPC connection to the event types specified in the message
+payload. See <<events>>.
+
+*Message:*
+
+A JSON-encoded array of event types to subscribe to.
+
+*Reply:*
 
 The reply consists of a single serialized map. The only property is
 +success (bool)+, indicating whether the subscription was successful (the
@@ -246,7 +290,15 @@ default) or whether a JSON parse error occurred.
 -------------------
 
 [[_outputs_reply]]
-=== OUTPUTS reply
+=== GET_OUTPUTS / OUTPUTS
+
+Get the list of current outputs.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The reply consists of a serialized list of outputs. Each output has the
 following properties:
@@ -257,7 +309,7 @@ active (boolean)::
 	Whether this output is currently active (has a valid mode).
 primary (boolean)::
 	Whether this output is currently the primary output.
-current_workspace (string)::
+current_workspace (string or null)::
 	The name of the current workspace that is visible on this output. +null+ if
 	the output is not active.
 rect (map)::
@@ -293,7 +345,15 @@ rect (map)::
 -------------------
 
 [[_tree_reply]]
-=== TREE reply
+=== GET_TREE / TREE
+
+Get the i3 layout tree.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The reply consists of a serialized tree. Each node in the tree (representing
 one container) has at least the properties listed below. While the nodes might
@@ -329,7 +389,7 @@ orientation (string)::
 	"vertical".
 	THIS FIELD IS OBSOLETE. It is still present, but your code should not
 	use it. Instead, rely on the layout field.
-percent (float)::
+percent (float or null)::
 	The percentage which this container takes in its parent. A value of
 	+null+ means that the percent property does not make sense for this
 	container, for example for the root container.
@@ -353,14 +413,15 @@ deco_rect (map)::
 geometry (map)::
 	The original geometry the window specified when i3 mapped it. Used when
 	switching a window to floating mode, for example.
-window (integer)::
+window (integer or null)::
 	The X11 window ID of the *actual client window* inside this container.
-	This field is set to null for split containers or otherwise empty
+	This field is set to +null+ for split containers or otherwise empty
 	containers. This ID corresponds to what xwininfo(1) and other
 	X11-related tools display (usually in hex).
 window_properties (map)::
 	This optional field contains all available X11 window properties from the
-	following list: *title*, *instance*, *class*, *window_role* and *transient_for*.
+	following list: *title*, *instance*, *class*, *window_role*, *machine*
+	and *transient_for*.
 window_type (string)::
 	The window type (_NET_WM_WINDOW_TYPE). Possible values are undefined, normal,
 	dialog, utility, toolbar, splash, menu, dropdown_menu, popup_menu, tooltip and
@@ -386,12 +447,18 @@ fullscreen_mode (integer)::
         +1+ (fullscreened on output) or
         +2+ (fullscreened globally).
     Note that all workspaces are considered fullscreened on their respective output.
-
+floating (string)::
+	Floating state of container.
+	Can be either "auto_on", "auto_off", "user_on" or "user_off"
 nodes (array of node)::
 	The tiling (i.e. non-floating) child containers of this node.
 floating_nodes (array of node)::
 	The floating child containers of this node. Only non-empty on nodes with
 	type +workspace+.
+scratchpad_state (string)::
+	Whether the window is not in the scratchpad ("none"), freshly moved to
+	the scratchpad but not yet resized ("fresh") or moved to the scratchpad
+	and resized ("changed").
 
 Please note that in the following example, I have left out some keys/values
 which are not relevant for the type of the node. Otherwise, the example would
@@ -532,7 +599,15 @@ JSON dump:
 -----------------------
 
 [[_marks_reply]]
-=== MARKS reply
+=== GET_MARKS / MARKS
+
+Gets the names of all currently set marks.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The reply consists of a single array of strings for each container that has a
 mark. A mark can only be set on one container, so the array is unique.
@@ -541,7 +616,15 @@ The order of that array is undefined.
 If no window has a mark the response will be the empty array [].
 
 [[_bar_config_reply]]
-=== BAR_CONFIG reply
+=== GET_BAR_CONFIG / BAR_CONFIG
+
+Gets the specified bar configuration or the names of all bar configurations if payload is empty.
+
+*Message:*
+
+No payload, or the ID of the bar whose configuration to retrieve.
+
+*Reply:*
 
 This can be used by third-party workspace bars (especially i3bar, but others
 are free to implement compatible alternatives) to get the +bar+ block
@@ -641,7 +724,15 @@ binding_mode_text/binding_mode_bg/binding_mode_border::
 --------------
 
 [[_version_reply]]
-=== VERSION reply
+=== GET_VERSION / VERSION
+
+Gets the i3 version.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The reply consists of a single JSON dictionary with the following keys:
 
@@ -674,7 +765,15 @@ loaded_config_file_name (string)::
 -------------------
 
 [[_binding_modes_reply]]
-=== BINDING_MODES reply
+=== GET_BINDING_MODES / BINDING_MODES
+
+Gets the names of all currently configured binding modes.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The reply consists of an array of all currently configured binding modes.
 
@@ -684,18 +783,66 @@ The reply consists of an array of all currently configured binding modes.
 ---------------------
 
 [[_config_reply]]
-=== CONFIG reply
+=== GET_CONFIG / CONFIG
 
-The config reply is a map which currently only contains the "config" member,
-which is a string containing the config file as loaded by i3 most recently.
+Returns the last loaded i3 config.
+
+*Message:*
+
+No payload.
+
+*Reply:*
+
+The config reply is a map which contains the following fields:
+
+config (string)::
+	The top-level config file contents that i3 has loaded most recently.
+	This field is kept for backwards compatibility. See +included_configs+
+	instead.
+included_configs (array of maps)::
+	i3 adds one entry to this array for each config file it loads, in
+	order. The first entry’s +raw_contents+ are identical to the +config+
+	field.
+
+Each +included_configs+ entry contains the following fields
+
+path (string)::
+	Absolute path name to the config file that i3 loaded.
+raw_contents (string)::
+	The raw contents of the file as i3 read them.
+variable_replaced_contents (string)::
+	The contents of the file after i3 replaced all variables. This is useful
+	for debugging variable replacement.
 
 *Example:*
 -------------------
-{ "config": "font pango:monospace 8\nbindsym Mod4+q exit\n" }
+{
+  "config": "include font.cfg\n",
+  "included_configs": [
+    {
+      "path": "/home/michael/configfiles/i3/config",
+      "raw_contents": "include font.cfg\n",
+      "variable_replaced_contents": "include font.cfg\n"
+    },
+    {
+      "path": "/home/michael/configfiles/i3/font.cfg",
+      "raw_contents": "set $font pango:monospace 8\nfont $font",
+      "variable_replaced_contents": "set pango:monospace 8 pango:monospace 8\nfont pango:monospace 8\n"
+    }
+  ],
+}
 -------------------
 
 [[_tick_reply]]
-=== TICK reply
+=== SEND_TICK / TICK
+
+Sends a tick event with the specified payload.
+
+*Message:*
+
+The payload of the tick event to send to IPC event listeners.
+
+*Reply:*
 
 The reply is a map containing the "success" member. After the reply was
 received, the tick event has been written to all IPC connections which subscribe
@@ -709,7 +856,15 @@ events generated prior to the +SEND_TICK+ message (happened-before relation).
 -------------------
 
 [[_sync_reply]]
-=== SYNC reply
+=== SYNC
+
+Sends an i3 sync event with the specified random value to the specified window.
+
+*Message:*
+
+A JSON-encoded map with the properties "rnd" and "window" (both integer).
+
+*Reply:*
 
 The reply is a map containing the "success" member. After the reply was
 received, the https://i3wm.org/docs/testsuite.html#i3_sync[i3 sync message] was
@@ -721,7 +876,15 @@ responded to.
 -------------------
 
 [[_binding_state_reply]]
-=== GET_BINDING_STATE reply
+=== GET_BINDING_STATE
+
+Request the current binding state, i.e. the currently active binding mode name.
+
+*Message:*
+
+No payload.
+
+*Reply:*
 
 The binding_state reply is a map which currently only contains the "name"
 member, which is the name of the currently active binding mode as a string.
diff --git a/docs/layout-saving b/docs/layout-saving
index 4f0ffccf5..380ffff8e 100644
--- a/docs/layout-saving
+++ b/docs/layout-saving
@@ -185,9 +185,9 @@ Therefore, if you just start Emacs via dmenu, it will not get swallowed by that
 container. Only if you start Emacs with the proper instance name (+emacs24
 --name notmuch+), it will get swallowed.
 
-You can match on "class", "instance", "window_role" and "title". All values are
-case-sensitive regular expressions (PCRE). Use +xprop(1)+ and click into a
-window to see its properties:
+You can match on "class", "instance", "window_role", "title" and "machine". All
+values are case-sensitive regular expressions (PCRE). Use +xprop(1)+ and click
+into a window to see its properties:
 
 --------------------------------------------------------------------------------
 $ xprop
diff --git a/docs/testsuite b/docs/testsuite
index 145da1586..d681549ce 100644
--- a/docs/testsuite
+++ b/docs/testsuite
@@ -481,7 +481,7 @@ an i3 crash resulting in the testcase being unable to communicate with i3 via
 IPC anymore.
 
 [[i3_sync]]
-== Appendix A: The i3 sync protocol
+== Appendix A: The I3_SYNC protocol
 
 Consider the following situation: You open two windows in your testcase, then
 you use +focus left+ and want to verify that the X11 focus has been updated
@@ -499,9 +499,9 @@ is($x->input_focus, $left->id, 'left window focused');
 However, the test fails. Sometimes. Apparently, there is a race condition in
 your test. If you think about it, this is because you are using two different
 pieces of software: You tell i3 to update focus, i3 confirms that, and then you
-ask X11 to give you the current focus. There is a certain time i3 needs to
-update the X11 state. If the testcase gets CPU time before X11 processed i3's
-requests, the test will fail.
+ask X11 to give you the current focus. There is a certain time that the X11
+server needs to process the requests from i3. If the testcase's request for the
+input focus is processed before i3's requests, the test will fail.
 
 image::i3-sync.png["Diagram of the race condition", title="Diagram of the race condition"]
 
@@ -531,10 +531,10 @@ less robust.
 
 The real solution for this problem is a mechanism which I call "the i3 sync
 protocol". The idea is to send a request (which does not modify state) via X11
-to i3 which will then be answered. Due to the request's position in the event
-queue (*after* all previous events), you can be sure that by the time you
-receive the reply, all other events have been dealt with by i3 (and, more
-importantly, X11).
+to i3 which will then be answered, again via X11. Because this answer is
+generated via an X11 request, it will be sent to the X11 server *after* all
+previous requests. Thus, you can be sure that by the time you receive the reply,
+all other events have been dealt with by i3 (and, more importantly, X11).
 
 image::i3-sync-working.png["Diagram of the i3 sync solution", title="Diagram of the i3 sync solution"]
 
@@ -569,7 +569,35 @@ i3 will then reply with the same ClientMessage, sent to the window specified in
 request. You should use a random value in +data[1]+ and check that you received
 the same one when getting the reply.
 
-== Appendix B: Socket activation
+== Appendix B: The sync IPC command
+
+The above I3_SYNC protocol allows to synchronise with i3. However, it is not
+enough for tests that also involve i3bar: There might still be messages from
+i3bar in-flight even after synchronising with i3. Thus, there also exists a sync
+IPC command, that is however not meant to be used directly. Instead, i3bar uses
+it for implementing the I3_SYNC protocol.
+
+The intended usage works like this:
+
+1. You send an I3_SYNC message to i3bar's window. See <<i3_sync>>.
+2. i3bar sends a SYNC IPC command to i3 with payload
+   +{"window":your-window-here,"rnd":your-random-value}+.
+3. i3 reacts to this IPC command as if it received an I3_SYNC request via X11.
+
+This protocol is used, for example, in t/525-i3bar-mouse-bindings.t: A mouse
+button press on i3bar is triggered. i3bar reacts to this by sending IPC commands
+to i3.
+
+The necessary synchronisation is achieved by sending an I3_SYNC event to i3bar:
+Because i3bar reacts with a sync IPC command to i3, all previous IPC commands from
+i3bar will be handled first. Because i3 reacts via X11, all previous X11
+requests from i3 will be handled by the X11 server first.
+
+The actual test also has to sync with i3 first due to how X11 handling works.
+For more details, refer to the documentation for +XAllowEvents+ with mode
++ReplayPointer+.
+
+== Appendix C: Socket activation
 
 Socket activation is a mechanism which was made popular by systemd, an init
 replacement. It basically describes creating a listening socket before starting
diff --git a/docs/userguide b/docs/userguide
index 2ad34184d..fe80ee016 100644
--- a/docs/userguide
+++ b/docs/userguide
@@ -3,9 +3,9 @@ i3 User’s Guide
 Michael Stapelberg <michael@i3wm.org>
 
 This document contains all the information you need to configure and use the i3
-window manager. If it does not, please check https://www.reddit.com/r/i3wm/
-first, then contact us on IRC (preferred) or post your question(s) on the
-mailing list.
+window manager. If it does not you can https://i3wm.org/contact/[contact us] on
+https://github.com/i3/i3/discussions[GitHub Discussions], IRC, or the mailing
+list.
 
 == Default keybindings
 
@@ -53,12 +53,23 @@ existing window (rotated displays).
 
 image:two_terminals.png[Two terminals]
 
-To move the focus between the two terminals, you can use the direction keys
-which you might know from the editor +vi+. However, in i3, your homerow is used
-for these keys (in +vi+, the keys are shifted to the left by one for
-compatibility with most keyboard layouts). Therefore, +$mod+j+ is left, +$mod+k+
-is down, +$mod+l+ is up and `$mod+;` is right. So, to switch between the
-terminals, use +$mod+k+ or +$mod+l+. Of course, you can also use the arrow keys.
+To move the focus between the two terminals, you can use the arrow keys. For
+convenience, the arrows are also available directly on the
+https://en.wikipedia.org/wiki/Touch_typing[keyboard’s home row] underneath your
+right hand:
+
+|===
+| `$mod+j` | left
+| `$mod+k` | down
+| `$mod+l` | up
+| `$mod+;` | right
+|===
+
+Note that this differs by one key from the popular text editor `vi`, which was
+https://twitter.com/hillelogram/status/1326600125569961991[developed on an
+ADM-3A terminal and therefore uses `hjkl` instead of `jkl;`] -- i3’s default is
+meant to require minimal finger movement, but some `vi` users change their i3
+config for consistency.
 
 At the moment, your workspace is split (it contains two terminals) in a
 specific direction (horizontal by default). Every window can be split
@@ -67,7 +78,7 @@ horizontally or vertically again, just like the workspace. The terminology is
 or browser) and "split container" for containers that consist of one or more
 windows.
 
-TODO: picture of the tree
+//TODO: picture of the tree
 
 To split a window vertically, press +$mod+v+ before you create the new window.
 To split it horizontally, press +$mod+h+.
@@ -308,6 +319,90 @@ include the following line in your config file:
 # i3 config file (v4)
 ---------------------
 
+[[include]]
+=== Include directive
+
+Since i3 v4.20, it is possible to include other configuration files from your i3
+configuration.
+
+*Syntax*:
+-----------------
+include <pattern>
+-----------------
+
+i3 expands `pattern` using shell-like word expansion, specifically using the
+https://manpages.debian.org/wordexp.3[`wordexp(3)` C standard library function].
+
+*Examples*:
+--------------------------------------------------------------------------------
+# Tilde expands to the user’s home directory:
+include ~/.config/i3/assignments.conf
+
+# Environment variables are expanded:
+include $HOME/.config/i3/assignments.conf
+
+# Wildcards are expanded:
+include ~/.config/i3/config.d/*.conf
+
+# Command substitution:
+include ~/.config/i3/`hostname`.conf
+
+# i3 loads each path only once, so including the i3 config will not result
+# in an endless loop, but in an error:
+include ~/.config/i3/config
+
+# i3 changes the working directory while parsing a config file
+# so that relative paths are interpreted relative to the directory
+# of the config file that contains the path:
+include assignments.conf
+--------------------------------------------------------------------------------
+
+If a specified file cannot be read, for example because of a lack of file
+permissions, or because of a dangling symlink, i3 will report an error and
+continue processing your remaining configuration.
+
+To list all loaded configuration files, run `i3 --moreversion`:
+
+--------------------------------------------------------------------------------
+% i3 --moreversion
+Binary i3 version:  4.19.2-87-gfcae64f7+ © 2009 Michael Stapelberg and contributors
+Running i3 version: 4.19.2-87-gfcae64f7+ (pid 963940)
+Loaded i3 config:
+  /tmp/i3.cfg (main) (last modified: 2021-05-13T16:42:31 CEST, 463 seconds ago)
+  /tmp/included.cfg (included) (last modified: 2021-05-13T16:42:43 CEST, 451 seconds ago)
+  /tmp/another.cfg (included) (last modified: 2021-05-13T16:42:46 CEST, 448 seconds ago)
+--------------------------------------------------------------------------------
+
+Variables are shared between all config files, but beware of the following limitation:
+
+* You can define a variable and use it within an included file.
+* You cannot use (in the parent file) a variable that was defined within an included file.
+
+This is a technical limitation: variable expansion happens in a separate stage
+before parsing include directives.
+
+Conceptually, included files can only add to the configuration, not undo the
+effects of already-processed configuration. For example, you can only add new
+key bindings, not overwrite or remove existing key bindings. This means:
+
+* The `include` directive is suitable for organizing large configurations into
+  separate files, possibly selecting files based on conditionals.
+
+* The `include` directive is not suitable for expressing “use the default
+  configuration with the following changes”. For that case, we still recommend
+  copying and modifying the default config.
+
+[NOTE]
+====
+Implementation-wise, i3 does not currently construct one big configuration from
+all `include` directives. Instead, i3’s config file parser interprets all
+configuration directives in its `parse_file()` function. When processing an
+`include` configuration directive, the parser recursively calls `parse_file()`.
+
+This means the evaluation order of files forms a tree, or one could say i3 uses
+depth-first traversal.
+====
+
 === Comments
 
 It is possible and recommended to use comments in your configuration file to
@@ -597,9 +692,10 @@ Default is +left+
 title_align left|center|right
 ---------------------------------------------
 
+[[default_border]]
 === Default border style for new windows
 
-This option determines which border style new windows will have. The default is
+This option determines which border style *new* windows will have.  The default is
 +normal+. Note that default_floating_border applies only to windows which are starting out as
 floating windows, e.g., dialog windows, but not windows that are floated later on.
 
@@ -1880,12 +1976,17 @@ bindsym $mod+x [class="Firefox" window_role="About"] kill
 # enable floating mode and move container to workspace 4
 for_window [class="^evil-app$"] floating enable, move container to workspace 4
 
+# enable window icons for all windows with extra horizontal padding of 1px
+for_window [all] title_window_icon padding 1px
+
 # move all floating windows to the scratchpad
 bindsym $mod+x [floating] move scratchpad
 ------------------------------------
 
 The criteria which are currently implemented are:
 
+all::
+	Matches all windows. This criterion requires no value.
 class::
 	Compares the window class (the second part of WM_CLASS). Use the
 	special value +\_\_focused__+ to match all windows having the same window
@@ -1902,6 +2003,10 @@ window_type::
 	Compare the window type (_NET_WM_WINDOW_TYPE). Possible values are
 	+normal+, +dialog+, +utility+, +toolbar+, +splash+, +menu+, +dropdown_menu+,
 	+popup_menu+, +tooltip+ and +notification+.
+machine::
+	Compares the name of the machine the client window is running on
+	(WM_CLIENT_MACHINE). Usually, it is equal to the hostname of the local
+	machine, but it may differ if remote X11 apps are used.
 id::
 	Compares the X11 window ID, which you can get via +xwininfo+ for example.
 title::
@@ -1939,9 +2044,9 @@ tiling_from::
 	tiling are matched. With "user", only windows that the user made tiling
 	are matched.
 
-The criteria +class+, +instance+, +role+, +title+, +workspace+ and +mark+ are
-actually regular expressions (PCRE). See +pcresyntax(3)+ or +perldoc perlre+ for
-information on how to use them.
+The criteria +class+, +instance+, +role+, +title+, +workspace+, +machine+ and
++mark+ are actually regular expressions (PCRE). See +pcresyntax(3)+ or +perldoc
+perlre+ for information on how to use them.
 
 [[exec]]
 === Executing applications (exec)
@@ -2281,9 +2386,8 @@ exhausting numbered ones and looks for numbered ones after exhausting named ones
 See <<move_to_outputs>> for how to move a container/workspace to a different
 RandR output.
 
-Workspace names are parsed as
-https://developer.gnome.org/pango/stable/pango-Markup.html[Pango markup]
-by i3bar.
+Workspace names are parsed as https://developer.gnome.org/pango/1.46/[Pango
+markup] by i3bar.
 
 [[back_and_forth]]
 To switch back to the previously focused workspace, use +workspace
@@ -2408,15 +2512,18 @@ To move a container to another RandR output (addressed by names like +LVDS1+ or
 
 *Syntax*:
 ------------------------------------------------------------
-move container to output left|right|down|up|current|primary|<output>
-move workspace to output left|right|down|up|current|primary|<output>
-------------------------------------------------------------
+move container to output left|right|down|up|current|primary|next|<output1> [output2]…
+move workspace to output left|right|down|up|current|primary|next|<output1> [output2]…
+-------------------------------------------------------------------------------------
 
 *Examples*:
 --------------------------------------------------------
 # Move the current workspace to the next output
 # (effectively toggles when you only have two outputs)
-bindsym $mod+x move workspace to output right
+bindsym $mod+x move workspace to output next
+
+# Cycle this workspace between outputs VGA1 and LVDS1 but not DVI0
+bindsym $mod+x move workspace to output VGA1 LVDS1
 
 # Put this window on the presentation output.
 bindsym $mod+x move container to output VGA1
@@ -2425,6 +2532,11 @@ bindsym $mod+x move container to output VGA1
 bindsym $mod+x move container to output primary
 --------------------------------------------------------
 
+If you specify more than one output, the container/workspace is cycled through
+them: If it is already in one of the outputs of the list, it will move to the
+next output in the list. If it is in an output not in the list, it will move to
+the first specified output. Non-existing outputs are skipped.
+
 Note that you might not have a primary output configured yet. To do so, run:
 -------------------------
 xrandr --output <output> --primary
@@ -2575,9 +2687,8 @@ unmark irssi
 
 By default, i3 will simply print the X11 window title. Using +title_format+,
 this can be customized by setting the format to the desired output. This
-directive supports
-https://developer.gnome.org/pango/stable/pango-Markup.html[Pango markup]
-and the following placeholders which will be replaced:
+directive supports https://developer.gnome.org/pango/1.46/[Pango markup] and the
+following placeholders which will be replaced:
 
 +%title+::
     For normal windows, this is the X11 window title (_NET_WM_NAME or WM_NAME
@@ -2590,6 +2701,9 @@ and the following placeholders which will be replaced:
 +%instance+::
     The X11 window instance (first part of WM_CLASS). This corresponds to the
     +instance+ criterion, see <<command_criteria>>.
++%machine+::
+    The X11 name of the machine (WM_CLIENT_MACHINE). This corresponds to the
+    +machine+ criterion, see <<command_criteria>>.
 
 Using the <<for_window>> directive, you can set the title format for any window
 based on <<command_criteria>>.
@@ -2611,6 +2725,32 @@ for_window [class=".*"] title_format "<b>%title</b>"
 for_window [class="(?i)firefox"] title_format "<span foreground='red'>%title</span>"
 -------------------------------------------------------------------------------------
 
+[[title_window_icon]]
+=== Window title icon
+
+By default, i3 does not display the window icon in the title bar.
+
+Starting with i3 v4.20, you can optionally enable window icons either for
+specific windows or for all windows (using the <<for_window>> directive).
+
+*Syntax*:
+-----------------------------
+title_window_icon <yes|no>
+title_window_icon padding <px>
+------------------------------
+
+*Examples*:
+-------------------------------------------------------------------------------------
+# show the window icon for the focused window to make it stand out
+bindsym $mod+p title_window_icon on
+
+# enable window icons for all windows
+for_window [all] title_window_icon on
+
+# enable window icons for all windows with extra horizontal padding
+for_window [all] title_window_icon padding 3px
+-------------------------------------------------------------------------------------
+
 === Changing border style
 
 To change the border of the current client, you can use +border normal+ to use the normal
@@ -2640,10 +2780,16 @@ border 1pixel
 bindsym $mod+t border normal 0
 # use no window title and a thick border
 bindsym $mod+y border pixel 3
+# use window title *and* a thick border
+bindsym $mod+y border normal 3
 # use neither window title nor border
 bindsym $mod+u border none
+# no border on VLC
+for_window [class="vlc"] border none
 ----------------------------------------------
 
+To change the default for all windows, see the directive <<default_border>>.
+
 [[shmlog]]
 === Enabling shared memory logging
 
diff --git a/etc/config b/etc/config
index ce22fd3d1..51902f080 100644
--- a/etc/config
+++ b/etc/config
@@ -17,6 +17,10 @@ font pango:monospace 8
 # text rendering and scalability on retina/hidpi displays (thanks to pango).
 #font pango:DejaVu Sans Mono 8
 
+# Start XDG autostart .desktop files using dex. See also
+# https://wiki.archlinux.org/index.php/XDG_Autostart
+exec --no-startup-id dex --autostart --environment i3
+
 # The combination of xss-lock, nm-applet and pactl is a popular choice, so
 # they are included here as an example. Modify as you see fit.
 
diff --git a/etc/config.keycodes b/etc/config.keycodes
index f76d5a714..11a7d46fd 100644
--- a/etc/config.keycodes
+++ b/etc/config.keycodes
@@ -18,6 +18,10 @@ font pango:monospace 8
 # text rendering and scalability on retina/hidpi displays (thanks to pango).
 #font pango:DejaVu Sans Mono 8
 
+# Start XDG autostart .desktop files using dex. See also
+# https://wiki.archlinux.org/index.php/XDG_Autostart
+exec --no-startup-id dex --autostart --environment i3
+
 # The combination of xss-lock, nm-applet and pactl is a popular choice, so
 # they are included here as an example. Modify as you see fit.
 
diff --git a/generate-command-parser.pl b/generate-command-parser.pl
index 77502db7e..cef4eda50 100755
--- a/generate-command-parser.pl
+++ b/generate-command-parser.pl
@@ -133,7 +133,7 @@ sub slurp {
 open(my $callfh, '>', "GENERATED_${prefix}_call.h");
 my $resultname = uc(substr($prefix, 0, 1)) . substr($prefix, 1) . 'ResultIR';
 say $callfh '#pragma once';
-say $callfh "static void GENERATED_call(const int call_identifier, struct $resultname *result) {";
+say $callfh "static void GENERATED_call(Match *current_match, struct stack *stack, const int call_identifier, struct $resultname *result) {";
 say $callfh '    switch (call_identifier) {';
 my $call_id = 0;
 for my $state (@keys) {
@@ -150,8 +150,8 @@ sub slurp {
         # calls to get_string(). Also replaces state names (like FOR_WINDOW)
         # with their ID (useful for cfg_criteria_init(FOR_WINDOW) e.g.).
         $cmd =~ s/$_/$statenum{$_}/g for @keys;
-        $cmd =~ s/\$([a-z_]+)/get_string("$1")/g;
-        $cmd =~ s/\&([a-z_]+)/get_long("$1")/g;
+        $cmd =~ s/\$([a-z_]+)/get_string(stack, "$1")/g;
+        $cmd =~ s/\&([a-z_]+)/get_long(stack, "$1")/g;
         # For debugging/testing, we print the call using printf() and thus need
         # to generate a format string. The format uses %d for <number>s,
         # literal numbers or state IDs and %s for NULL, <string>s and literal
@@ -175,9 +175,9 @@ sub slurp {
         say $callfh '#ifndef TEST_PARSER';
         my $real_cmd = $cmd;
         if ($real_cmd =~ /\(\)/) {
-            $real_cmd =~ s/\(/(&current_match, result/;
+            $real_cmd =~ s/\(/(current_match, result/;
         } else {
-            $real_cmd =~ s/\(/(&current_match, result, /;
+            $real_cmd =~ s/\(/(current_match, result, /;
         }
         say $callfh "             $real_cmd;";
         say $callfh '#else';
diff --git a/i3-dmenu-desktop b/i3-dmenu-desktop
index 07fe83360..09670f652 100755
--- a/i3-dmenu-desktop
+++ b/i3-dmenu-desktop
@@ -154,6 +154,8 @@ find(
         },
         no_chdir => 1,
         follow_fast => 1,
+        # Ignore any duplicate files and directories and proceed normally:
+        follow_skip => 2,
     },
     @searchdirs
 );
diff --git a/i3-dump-log/main.c b/i3-dump-log/main.c
index e58b0c379..0ce222647 100644
--- a/i3-dump-log/main.c
+++ b/i3-dump-log/main.c
@@ -25,10 +25,10 @@
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
 
-#if !defined(__OpenBSD__)
-static uint32_t offset_next_write;
-#endif
 static uint32_t wrap_count;
 
 static i3_shmlog_header *header;
@@ -36,12 +36,6 @@ static char *logbuffer,
     *walk;
 static int ipcfd = -1;
 
-static volatile bool interrupted = false;
-
-static void sighandler(int signal) {
-    interrupted = true;
-}
-
 static void disable_shmlog(void) {
     const char *disablecmd = "debuglog off; shmlog off";
     if (ipc_send_message(ipcfd, strlen(disablecmd),
@@ -188,22 +182,25 @@ int main(int argc, char *argv[]) {
 
     /* NB: While we must never write, we need O_RDWR for the pthread condvar. */
     int logbuffer_shm = shm_open(shmname, O_RDWR, 0);
-    if (logbuffer_shm == -1)
+    if (logbuffer_shm == -1) {
         err(EXIT_FAILURE, "Could not shm_open SHM segment for the i3 log (%s)", shmname);
+    }
 
-    if (fstat(logbuffer_shm, &statbuf) != 0)
+    if (fstat(logbuffer_shm, &statbuf) != 0) {
         err(EXIT_FAILURE, "stat(%s)", shmname);
+    }
 
-    /* NB: While we must never write, we need PROT_WRITE for the pthread condvar. */
-    logbuffer = mmap(NULL, statbuf.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, logbuffer_shm, 0);
-    if (logbuffer == MAP_FAILED)
+    logbuffer = mmap(NULL, statbuf.st_size, PROT_READ, MAP_SHARED, logbuffer_shm, 0);
+    if (logbuffer == MAP_FAILED) {
         err(EXIT_FAILURE, "Could not mmap SHM segment for the i3 log");
+    }
 
     header = (i3_shmlog_header *)logbuffer;
 
-    if (verbose)
+    if (verbose) {
         printf("next_write = %d, last_wrap = %d, logbuffer_size = %d, shmname = %s\n",
                header->offset_next_write, header->offset_last_wrap, header->size, shmname);
+    }
     free(shmname);
     walk = logbuffer + header->offset_next_write;
 
@@ -233,25 +230,38 @@ int main(int argc, char *argv[]) {
         return 0;
     }
 
-    /* Handle SIGINT gracefully to invoke atexit handlers, if any. */
-    struct sigaction action;
-    action.sa_handler = sighandler;
-    sigemptyset(&action.sa_mask);
-    action.sa_flags = 0;
-    sigaction(SIGINT, &action, NULL);
-
-    /* Since pthread_cond_wait() expects a mutex, we need to provide one.
-     * To not lock i3 (that’s bad, mhkay?) we just define one outside of
-     * the shared memory. */
-    pthread_mutex_t dummy_mutex = PTHREAD_MUTEX_INITIALIZER;
-    pthread_mutex_lock(&dummy_mutex);
-    while (!interrupted) {
-        pthread_cond_wait(&(header->condvar), &dummy_mutex);
-        /* If this was not a spurious wakeup, print the new lines. */
-        if (header->offset_next_write != offset_next_write) {
-            offset_next_write = header->offset_next_write;
-            print_till_end();
+    char *log_stream_socket_path = root_atom_contents("I3_LOG_STREAM_SOCKET_PATH", NULL, 0);
+    if (log_stream_socket_path == NULL) {
+        errx(EXIT_FAILURE, "could not determine i3 log stream socket path: possible i3-dump-log and i3 version mismatch");
+    }
+
+    int sockfd = socket(AF_LOCAL, SOCK_STREAM, 0);
+    if (sockfd == -1) {
+        err(EXIT_FAILURE, "Could not create socket");
+    }
+
+    (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
+
+    struct sockaddr_un addr;
+    memset(&addr, 0, sizeof(struct sockaddr_un));
+    addr.sun_family = AF_LOCAL;
+    strncpy(addr.sun_path, log_stream_socket_path, sizeof(addr.sun_path) - 1);
+    if (connect(sockfd, (const struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) {
+        err(EXIT_FAILURE, "Could not connect to i3 on socket %s", log_stream_socket_path);
+    }
+
+    /* Same size as the buffer used in log.c vlog(): */
+    char buf[4096];
+    for (;;) {
+        const int n = read(sockfd, buf, sizeof(buf));
+        if (n == -1) {
+            err(EXIT_FAILURE, "read(log-stream-socket):");
+        }
+        if (n == 0) {
+            exit(0); /* i3 closed the socket */
         }
+        buf[n] = '\0';
+        swrite(STDOUT_FILENO, buf, n);
     }
 
 #endif
diff --git a/i3-msg/main.c b/i3-msg/main.c
index c1c8bb81b..239ac46fb 100644
--- a/i3-msg/main.c
+++ b/i3-msg/main.c
@@ -156,6 +156,7 @@ int main(int argc, char *argv[]) {
     char *payload = NULL;
     bool quiet = false;
     bool monitor = false;
+    bool raw_reply = false;
 
     static struct option long_options[] = {
         {"socket", required_argument, 0, 's'},
@@ -164,9 +165,10 @@ int main(int argc, char *argv[]) {
         {"quiet", no_argument, 0, 'q'},
         {"monitor", no_argument, 0, 'm'},
         {"help", no_argument, 0, 'h'},
+        {"raw", no_argument, 0, 'r'},
         {0, 0, 0, 0}};
 
-    char *options_string = "s:t:vhqm";
+    char *options_string = "s:t:vhqmr";
 
     while ((o = getopt_long(argc, argv, options_string, long_options, &option_index)) != -1) {
         if (o == 's') {
@@ -217,6 +219,8 @@ int main(int argc, char *argv[]) {
             return 0;
         } else if (o == '?') {
             exit(EXIT_FAILURE);
+        } else if (o == 'r') {
+            raw_reply = true;
         }
     }
 
@@ -262,32 +266,38 @@ int main(int argc, char *argv[]) {
     /* For the reply of commands, have a look if that command was successful.
      * If not, nicely format the error message. */
     if (reply_type == I3_IPC_REPLY_TYPE_COMMAND) {
-        yajl_handle handle = yajl_alloc(&reply_callbacks, NULL, NULL);
-        yajl_status state = yajl_parse(handle, (const unsigned char *)reply, reply_length);
-        yajl_free(handle);
-
-        switch (state) {
-            case yajl_status_ok:
-                break;
-            case yajl_status_client_canceled:
-            case yajl_status_error:
-                errx(EXIT_FAILURE, "IPC: Could not parse JSON reply.");
+        if (!raw_reply) {
+            yajl_handle handle = yajl_alloc(&reply_callbacks, NULL, NULL);
+            yajl_status state = yajl_parse(handle, (const unsigned char *)reply, reply_length);
+            yajl_free(handle);
+
+            switch (state) {
+                case yajl_status_ok:
+                    break;
+                case yajl_status_client_canceled:
+                case yajl_status_error:
+                    errx(EXIT_FAILURE, "IPC: Could not parse JSON reply.");
+            }
         }
 
-        if (!quiet) {
+        if (!quiet || raw_reply) {
             printf("%.*s\n", reply_length, reply);
         }
     } else if (reply_type == I3_IPC_REPLY_TYPE_CONFIG) {
-        yajl_handle handle = yajl_alloc(&config_callbacks, NULL, NULL);
-        yajl_status state = yajl_parse(handle, (const unsigned char *)reply, reply_length);
-        yajl_free(handle);
-
-        switch (state) {
-            case yajl_status_ok:
-                break;
-            case yajl_status_client_canceled:
-            case yajl_status_error:
-                errx(EXIT_FAILURE, "IPC: Could not parse JSON reply.");
+        if (raw_reply) {
+            printf("%.*s\n", reply_length, reply);
+        } else {
+            yajl_handle handle = yajl_alloc(&config_callbacks, NULL, NULL);
+            yajl_status state = yajl_parse(handle, (const unsigned char *)reply, reply_length);
+            yajl_free(handle);
+
+            switch (state) {
+                case yajl_status_ok:
+                    break;
+                case yajl_status_client_canceled:
+                case yajl_status_error:
+                    errx(EXIT_FAILURE, "IPC: Could not parse JSON reply.");
+            }
         }
     } else if (reply_type == I3_IPC_REPLY_TYPE_SUBSCRIBE) {
         do {
diff --git a/i3-nagbar/main.c b/i3-nagbar/main.c
index b13ee1343..7d9c0901f 100644
--- a/i3-nagbar/main.c
+++ b/i3-nagbar/main.c
@@ -266,13 +266,9 @@ static int handle_expose(xcb_connection_t *conn, xcb_expose_event_t *event) {
 }
 
 /**
- * Return the position and size the i3-nagbar window should use.
- * This will be the primary output or a fallback if it cannot be determined.
+ * Tries to position the rectangle on the primary output.
  */
-static xcb_rectangle_t get_window_position(void) {
-    /* Default values if we cannot determine the primary output or its CRTC info. */
-    xcb_rectangle_t result = (xcb_rectangle_t){50, 50, 500, font.height + 2 * MSG_PADDING + BAR_BORDER};
-
+static void set_window_position_primary(xcb_rectangle_t *result) {
     xcb_randr_get_screen_resources_current_cookie_t rcookie = xcb_randr_get_screen_resources_current(conn, root);
     xcb_randr_get_output_primary_cookie_t pcookie = xcb_randr_get_output_primary(conn, root);
 
@@ -314,14 +310,61 @@ static xcb_rectangle_t get_window_position(void) {
         goto free_resources;
     }
 
-    result.x = crtc->x;
-    result.y = crtc->y;
+    result->x = crtc->x;
+    result->y = crtc->y;
     goto free_resources;
 
 free_resources:
     free(res);
     free(primary);
-    return result;
+}
+
+/**
+ * Tries to position the rectangle on the output with input focus.
+ * If unsuccessful, try to position on primary output.
+ */
+static void set_window_position_focus(xcb_rectangle_t *result) {
+    bool success = false;
+    xcb_get_input_focus_reply_t *input_focus = NULL;
+    xcb_get_geometry_reply_t *geometry = NULL;
+    xcb_translate_coordinates_reply_t *coordinates = NULL;
+
+    /* To avoid the input window disappearing while determining its position */
+    xcb_grab_server(conn);
+
+    input_focus = xcb_get_input_focus_reply(conn, xcb_get_input_focus(conn), NULL);
+    if (input_focus == NULL || input_focus->focus == XCB_NONE) {
+        LOG("Failed to receive the current input focus or no window has the input focus right now.\n");
+        goto free_resources;
+    }
+
+    geometry = xcb_get_geometry_reply(conn, xcb_get_geometry(conn, input_focus->focus), NULL);
+    if (geometry == NULL) {
+        LOG("Failed to received window geometry.\n");
+        goto free_resources;
+    }
+
+    coordinates = xcb_translate_coordinates_reply(
+        conn, xcb_translate_coordinates(conn, input_focus->focus, root, geometry->x, geometry->y), NULL);
+    if (coordinates == NULL) {
+        LOG("Failed to translate coordinates.\n");
+        goto free_resources;
+    }
+
+    LOG("Found current focus at x = %i / y = %i.\n", coordinates->dst_x, coordinates->dst_y);
+    result->x = coordinates->dst_x;
+    result->y = coordinates->dst_y;
+    success = true;
+
+free_resources:
+    xcb_ungrab_server(conn);
+    free(input_focus);
+    free(coordinates);
+    free(geometry);
+    if (!success) {
+        LOG("Could not position on focused output, trying to position on primary output.\n");
+        set_window_position_primary(result);
+    }
 }
 
 int main(int argc, char *argv[]) {
@@ -360,6 +403,7 @@ int main(int argc, char *argv[]) {
 
     argv0 = argv[0];
 
+    bool position_on_primary = false;
     char *pattern = sstrdup("pango:monospace 8");
     int o, option_index = 0;
     enum { TYPE_ERROR = 0,
@@ -373,9 +417,10 @@ int main(int argc, char *argv[]) {
         {"help", no_argument, 0, 'h'},
         {"message", required_argument, 0, 'm'},
         {"type", required_argument, 0, 't'},
+        {"primary", no_argument, 0, 'p'},
         {0, 0, 0, 0}};
 
-    char *options_string = "b:B:f:m:t:vh";
+    char *options_string = "b:B:f:m:t:vhp";
 
     prompt = i3string_from_utf8("Please do not run this program.");
 
@@ -399,8 +444,11 @@ int main(int argc, char *argv[]) {
             case 'h':
                 free(pattern);
                 printf("i3-nagbar " I3_VERSION "\n");
-                printf("i3-nagbar [-m <message>] [-b <button> <action>] [-B <button> <action>] [-t warning|error] [-f <font>] [-v]\n");
+                printf("i3-nagbar [-m <message>] [-b <button> <action>] [-B <button> <action>] [-t warning|error] [-f <font>] [-v] [-p]\n");
                 return 0;
+            case 'p':
+                position_on_primary = true;
+                break;
             case 'b':
             case 'B':
                 buttons = srealloc(buttons, sizeof(button_t) * (buttoncnt + 1));
@@ -464,7 +512,13 @@ int main(int argc, char *argv[]) {
         err(EXIT_FAILURE, "pledge");
 #endif
 
-    xcb_rectangle_t win_pos = get_window_position();
+    /* Default values if we cannot determine the preferred window position. */
+    xcb_rectangle_t win_pos = (xcb_rectangle_t){50, 50, 500, font.height + 2 * MSG_PADDING + BAR_BORDER};
+    if (position_on_primary) {
+        set_window_position_primary(&win_pos);
+    } else {
+        set_window_position_focus(&win_pos);
+    }
 
     xcb_cursor_context_t *cursor_ctx;
     if (xcb_cursor_context_new(conn, root_screen, &cursor_ctx) < 0) {
diff --git a/i3-sensible-terminal b/i3-sensible-terminal
index c3a2e4e0c..fa1443c40 100755
--- a/i3-sensible-terminal
+++ b/i3-sensible-terminal
@@ -8,7 +8,13 @@
 # We welcome patches that add distribution-specific mechanisms to find the
 # preferred terminal emulator. On Debian, there is the x-terminal-emulator
 # symlink for example.
-for terminal in "$TERMINAL" x-terminal-emulator urxvt rxvt termit terminator Eterm aterm uxterm xterm gnome-terminal roxterm xfce4-terminal termite lxterminal mate-terminal terminology st qterminal lilyterm tilix terminix konsole kitty guake tilda alacritty hyper; do
+#
+# Invariants:
+# 1. $TERMINAL must come first
+# 2. Distribution-specific mechanisms come next, e.g. x-terminal-emulator
+# 3. The terminal emulator with best accessibility comes first.
+# 4. No order is guaranteed/desired for the remaining terminal emulators.
+for terminal in "$TERMINAL" x-terminal-emulator mate-terminal gnome-terminal terminator xfce4-terminal urxvt rxvt termit Eterm aterm uxterm xterm roxterm termite lxterminal terminology st qterminal lilyterm tilix terminix konsole kitty guake tilda alacritty hyper; do
     if command -v "$terminal" > /dev/null 2>&1; then
         exec "$terminal" "$@"
     fi
diff --git a/i3bar/include/child.h b/i3bar/include/child.h
index adc638bed..ae523bc0f 100644
--- a/i3bar/include/child.h
+++ b/i3bar/include/child.h
@@ -42,6 +42,12 @@ typedef struct {
     bool click_events_init;
 } i3bar_child;
 
+/*
+ * Remove all blocks from the given statusline.
+ * If free_resources is set, the fields of each status block will be free'd.
+ */
+void clear_statusline(struct statusline_head *head, bool free_resources);
+
 /*
  * Start a child process with the specified command and reroute stdin.
  * We actually start a $SHELL to execute the command so we don't have to care
diff --git a/i3bar/include/configuration.h b/i3bar/include/configuration.h
index 589c63967..346d5b261 100644
--- a/i3bar/include/configuration.h
+++ b/i3bar/include/configuration.h
@@ -75,6 +75,13 @@ extern config_t config;
  */
 void parse_config_json(char *json);
 
+/**
+ * Start parsing the received bar configuration list. The only usecase right
+ * now is to automatically get the first bar id.
+ *
+ */
+void parse_get_first_i3bar_config(char *json);
+
 /**
  * free()s the color strings as soon as they are not needed anymore.
  *
diff --git a/i3bar/include/ipc.h b/i3bar/include/ipc.h
index 5056e5f37..2ce072150 100644
--- a/i3bar/include/ipc.h
+++ b/i3bar/include/ipc.h
@@ -18,7 +18,7 @@
  * socket_path must be a valid path to the ipc_socket of i3
  *
  */
-int init_connection(const char *socket_path);
+void init_connection(const char *socket_path);
 
 /*
  * Destroy the connection to i3.
diff --git a/i3bar/src/child.c b/i3bar/src/child.c
index bece314f2..df4c66016 100644
--- a/i3bar/src/child.c
+++ b/i3bar/src/child.c
@@ -27,7 +27,7 @@
 #include <yajl/yajl_parse.h>
 
 /* Global variables for child_*() */
-i3bar_child child;
+i3bar_child child = {0};
 #define DLOG_CHILD DLOG("%s: pid=%ld stopped=%d stop_signal=%d cont_signal=%d click_events=%d click_events_init=%d\n", \
                         __func__, (long)child.pid, child.stopped, child.stop_signal, child.cont_signal, child.click_events, child.click_events_init)
 
@@ -66,7 +66,7 @@ int child_stdin;
  * Remove all blocks from the given statusline.
  * If free_resources is set, the fields of each status block will be free'd.
  */
-static void clear_statusline(struct statusline_head *head, bool free_resources) {
+void clear_statusline(struct statusline_head *head, bool free_resources) {
     struct status_block *first;
     while (!TAILQ_EMPTY(head)) {
         first = TAILQ_FIRST(head);
@@ -139,6 +139,10 @@ static void cleanup(void) {
     if (stdin_io != NULL) {
         ev_io_stop(main_loop, stdin_io);
         FREE(stdin_io);
+        close(stdin_fd);
+        stdin_fd = 0;
+        close(child_stdin);
+        child_stdin = 0;
     }
 
     if (child_sig != NULL) {
diff --git a/i3bar/src/config.c b/i3bar/src/config.c
index c96277902..78f53d9f1 100644
--- a/i3bar/src/config.c
+++ b/i3bar/src/config.c
@@ -184,7 +184,6 @@ static int config_string_cb(void *params_, const unsigned char *val, size_t _len
 
     if (!strcmp(cur_key, "status_command")) {
         DLOG("command = %.*s\n", len, val);
-        FREE(config.command);
         sasprintf(&config.command, "%.*s", len, val);
         return 1;
     }
@@ -373,14 +372,12 @@ static yajl_callbacks outputs_callbacks = {
  *
  */
 void parse_config_json(char *json) {
-    yajl_handle handle;
-    yajl_status state;
-    handle = yajl_alloc(&outputs_callbacks, NULL, NULL);
+    yajl_handle handle = yajl_alloc(&outputs_callbacks, NULL, NULL);
 
     TAILQ_INIT(&(config.bindings));
     TAILQ_INIT(&(config.tray_outputs));
 
-    state = yajl_parse(handle, (const unsigned char *)json, strlen(json));
+    yajl_status state = yajl_parse(handle, (const unsigned char *)json, strlen(json));
 
     /* FIXME: Proper error handling for JSON parsing */
     switch (state) {
@@ -396,6 +393,25 @@ void parse_config_json(char *json) {
     yajl_free(handle);
 }
 
+static int i3bar_config_string_cb(void *params_, const unsigned char *val, size_t _len) {
+    sasprintf(&config.bar_id, "%.*s", (int)_len, val);
+    return 0; /* Stop parsing */
+}
+
+/*
+ * Start parsing the received bar configuration list. The only usecase right
+ * now is to automatically get the first bar id.
+ *
+ */
+void parse_get_first_i3bar_config(char *json) {
+    yajl_callbacks configs_callbacks = {
+        .yajl_string = i3bar_config_string_cb,
+    };
+    yajl_handle handle = yajl_alloc(&configs_callbacks, NULL, NULL);
+    yajl_parse(handle, (const unsigned char *)json, strlen(json));
+    yajl_free(handle);
+}
+
 /*
  * free()s the color strings as soon as they are not needed anymore.
  *
diff --git a/i3bar/src/ipc.c b/i3bar/src/ipc.c
index f2c105ac3..0e12eafa7 100644
--- a/i3bar/src/ipc.c
+++ b/i3bar/src/ipc.c
@@ -85,6 +85,20 @@ static void got_output_reply(char *reply) {
  *
  */
 static void got_bar_config(char *reply) {
+    if (!config.bar_id) {
+        DLOG("Received bar list \"%s\"\n", reply);
+        parse_get_first_i3bar_config(reply);
+
+        if (!config.bar_id) {
+            ELOG("No bar configuration found, please configure a bar block in your i3 config file.\n");
+            exit(EXIT_FAILURE);
+        }
+
+        LOG("Using first bar config: %s. Use --bar_id to manually select a different bar configuration.\n", config.bar_id);
+        i3_send_msg(I3_IPC_MESSAGE_TYPE_GET_BAR_CONFIG, config.bar_id);
+        return;
+    }
+
     DLOG("Received bar config \"%s\"\n", reply);
     /* We initiate the main function by requesting infos about the outputs and
      * workspaces. Everything else (creating the bars, showing the right workspace-
@@ -141,9 +155,6 @@ static void got_workspace_event(char *event) {
 static void got_output_event(char *event) {
     DLOG("Got output event!\n");
     i3_send_msg(I3_IPC_MESSAGE_TYPE_GET_OUTPUTS, NULL);
-    if (!config.disable_ws) {
-        i3_send_msg(I3_IPC_MESSAGE_TYPE_GET_WORKSPACES, NULL);
-    }
 }
 
 /*
@@ -156,6 +167,15 @@ static void got_mode_event(char *event) {
     draw_bars(false);
 }
 
+static bool strings_differ(char *a, char *b) {
+    const bool a_null = (a == NULL);
+    const bool b_null = (b == NULL);
+    if (a_null != b_null) {
+        return true;
+    }
+    return strcmp(a, b) != 0;
+}
+
 /*
  * Called, when a barconfig_update event arrives (i.e. i3 changed the bar hidden_state or mode)
  *
@@ -176,8 +196,11 @@ static void got_bar_config_update(char *event) {
 
     /* update the configuration with the received settings */
     DLOG("Received bar config update \"%s\"\n", event);
-    char *old_command = config.command ? sstrdup(config.command) : NULL;
+
+    char *old_command = config.command;
+    config.command = NULL;
     bar_display_mode_t old_mode = config.hide_on_modifier;
+
     parse_config_json(event);
     if (old_mode != config.hide_on_modifier) {
         reconfig_windows(true);
@@ -188,8 +211,9 @@ static void got_bar_config_update(char *event) {
     init_colors(&(config.colors));
 
     /* restart status command process */
-    if (old_command && strcmp(old_command, config.command) != 0) {
+    if (strings_differ(old_command, config.command)) {
         kill_child();
+        clear_statusline(&statusline_head, true);
         start_child(config.command);
     }
     free(old_command);
@@ -328,13 +352,12 @@ int i3_send_msg(uint32_t type, const char *payload) {
  * socket_path must be a valid path to the ipc_socket of i3
  *
  */
-int init_connection(const char *socket_path) {
+void init_connection(const char *socket_path) {
     sock_path = socket_path;
     int sockfd = ipc_connect(socket_path);
     i3_connection = smalloc(sizeof(ev_io));
     ev_io_init(i3_connection, &got_data, sockfd, EV_READ);
     ev_io_start(main_loop, i3_connection);
-    return 1;
 }
 
 /*
diff --git a/i3bar/src/main.c b/i3bar/src/main.c
index 4e729341b..4e93bb027 100644
--- a/i3bar/src/main.c
+++ b/i3bar/src/main.c
@@ -56,9 +56,9 @@ static char *expand_path(char *path) {
 }
 
 static void print_usage(char *elf_name) {
-    printf("Usage: %s -b bar_id [-s sock_path] [-t] [-h] [-v]\n", elf_name);
+    printf("Usage: %s [-b bar_id] [-s sock_path] [-t] [-h] [-v] [-V]\n", elf_name);
     printf("\n");
-    printf("-b, --bar_id       <bar_id>\tBar ID for which to get the configuration\n");
+    printf("-b, --bar_id       <bar_id>\tBar ID for which to get the configuration, defaults to the first bar from the i3 config\n");
     printf("-s, --socket       <sock_path>\tConnect to i3 via <sock_path>\n");
     printf("-t, --transparency Enable transparency (RGBA colors)\n");
     printf("-h, --help         Display this help message and exit\n");
@@ -128,17 +128,12 @@ int main(int argc, char **argv) {
                 break;
             default:
                 print_usage(argv[0]);
-                exit(EXIT_SUCCESS);
+                exit(EXIT_FAILURE);
                 break;
         }
     }
 
-    if (!config.bar_id) {
-        /* TODO: maybe we want -f which will automatically ask i3 for the first
-         * configured bar (and error out if there are too many)? */
-        ELOG("No bar_id passed. Please let i3 start i3bar or specify --bar_id\n");
-        exit(EXIT_FAILURE);
-    }
+    LOG("i3bar version " I3_VERSION "\n");
 
     main_loop = ev_default_loop(0); /* needed in init_xcb_early */
     char *atom_sock_path = init_xcb_early();
@@ -166,10 +161,13 @@ int main(int argc, char **argv) {
     init_dpi();
 
     init_outputs();
-    if (init_connection(socket_path)) {
-        /* Request the bar configuration. When it arrives, we fill the config array. */
-        i3_send_msg(I3_IPC_MESSAGE_TYPE_GET_BAR_CONFIG, config.bar_id);
-    }
+
+    init_connection(socket_path);
+    /* Request the bar configuration. When it arrives, we fill the config
+     * array. In case that config.bar_id is empty, we will receive a list of
+     * available configs and then request the configuration for the first bar.
+     * See got_bar_config for more. */
+    i3_send_msg(I3_IPC_MESSAGE_TYPE_GET_BAR_CONFIG, config.bar_id);
     free(socket_path);
 
     /* We listen to SIGTERM/QUIT/INT and try to exit cleanly, by stopping the main loop.
diff --git a/i3bar/src/xcb.c b/i3bar/src/xcb.c
index 89b34102a..e56beb36f 100644
--- a/i3bar/src/xcb.c
+++ b/i3bar/src/xcb.c
@@ -1540,7 +1540,6 @@ void clean_xcb(void) {
     free_font();
 
     xcb_free_cursor(xcb_connection, cursor);
-    xcb_flush(xcb_connection);
     xcb_aux_sync(xcb_connection);
     xcb_disconnect(xcb_connection);
 
diff --git a/include/all.h b/include/all.h
index 551119441..b9a1a7a97 100644
--- a/include/all.h
+++ b/include/all.h
@@ -56,7 +56,6 @@
 #include "render.h"
 #include "window.h"
 #include "match.h"
-#include "cmdparse.h"
 #include "xcursor.h"
 #include "resize.h"
 #include "sighandler.h"
diff --git a/include/cmdparse.h b/include/cmdparse.h
deleted file mode 100644
index a2cbb17ea..000000000
--- a/include/cmdparse.h
+++ /dev/null
@@ -1,14 +0,0 @@
-/*
- * vim:ts=4:sw=4:expandtab
- *
- * i3 - an improved dynamic tiling window manager
- * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
- *
- * cmdparse.y: the parser for commands you send to i3 (or bind on keys)
- *
- */
-#pragma once
-
-#include <config.h>
-
-char *parse_cmd(const char *new);
diff --git a/include/commands.h b/include/commands.h
index 4b2f99bc2..8dca3d578 100644
--- a/include/commands.h
+++ b/include/commands.h
@@ -138,7 +138,7 @@ void cmd_mode(I3_CMD, const char *mode);
  * Implementation of 'move [window|container] [to] output <str>'.
  *
  */
-void cmd_move_con_to_output(I3_CMD, const char *name);
+void cmd_move_con_to_output(I3_CMD, const char *name, bool move_workspace);
 
 /**
  * Implementation of 'move [window|container] [to] mark <str>'.
@@ -152,12 +152,6 @@ void cmd_move_con_to_mark(I3_CMD, const char *mark);
  */
 void cmd_floating(I3_CMD, const char *floating_mode);
 
-/**
- * Implementation of 'move workspace to [output] <str>'.
- *
- */
-void cmd_move_workspace_to_output(I3_CMD, const char *name);
-
 /**
  * Implementation of 'split v|h|t|vertical|horizontal|toggle'.
  *
@@ -343,3 +337,9 @@ void cmd_debuglog(I3_CMD, const char *argument);
  *
  */
 void cmd_gaps(I3_CMD, const char *type, const char *scope, const char *mode, const char *value);
+
+/**
+ * Implementation of 'title_window_icon <yes|no>' and 'title_window_icon padding <px>'
+ *
+ */
+void cmd_title_window_icon(I3_CMD, const char *enable, int padding);
diff --git a/include/config_directives.h b/include/config_directives.h
index e8d4bd2d5..c6a600619 100644
--- a/include/config_directives.h
+++ b/include/config_directives.h
@@ -39,6 +39,7 @@ CFGFUN(criteria_init, int _state);
 CFGFUN(criteria_add, const char *ctype, const char *cvalue);
 CFGFUN(criteria_pop_state);
 
+CFGFUN(include, const char *pattern);
 CFGFUN(font, const char *font);
 CFGFUN(exec, const char *exectype, const char *no_startup_id, const char *command);
 CFGFUN(for_window, const char *command);
diff --git a/include/config_parser.h b/include/config_parser.h
index 009538f2d..00d01e459 100644
--- a/include/config_parser.h
+++ b/include/config_parser.h
@@ -16,6 +16,50 @@
 SLIST_HEAD(variables_head, Variable);
 extern pid_t config_error_nagbar_pid;
 
+struct stack_entry {
+    /* Just a pointer, not dynamically allocated. */
+    const char *identifier;
+    enum {
+        STACK_STR = 0,
+        STACK_LONG = 1,
+    } type;
+    union {
+        char *str;
+        long num;
+    } val;
+};
+
+struct stack {
+    struct stack_entry stack[10];
+};
+
+struct parser_ctx {
+    bool use_nagbar;
+    bool assume_v4;
+
+    int state;
+    Match current_match;
+
+    /* A list which contains the states that lead to the current state, e.g.
+   * INITIAL, WORKSPACE_LAYOUT.
+   * When jumping back to INITIAL, statelist_idx will simply be set to 1
+   * (likewise for other states, e.g. MODE or BAR).
+   * This list is used to process the nearest error token. */
+    int statelist[10];
+    /* NB: statelist_idx points to where the next entry will be inserted */
+    int statelist_idx;
+
+    /*******************************************************************************
+   * The (small) stack where identified literals are stored during the parsing
+   * of a single config directive (like $workspace).
+   ******************************************************************************/
+    struct stack *stack;
+
+    struct variables_head variables;
+
+    bool has_errors;
+};
+
 /**
  * An intermediate reprsentation of the result of a parse_config call.
  * Currently unused, but the JSON output will be useful in the future when we
@@ -23,22 +67,34 @@ extern pid_t config_error_nagbar_pid;
  *
  */
 struct ConfigResultIR {
-    /* The JSON generator to append a reply to. */
-    yajl_gen json_gen;
+    struct parser_ctx *ctx;
 
     /* The next state to transition to. Passed to the function so that we can
      * determine the next state as a result of a function call, like
      * cfg_criteria_pop_state() does. */
     int next_state;
-};
 
-struct ConfigResultIR *parse_config(const char *input, struct context *context);
+    /* Whether any error happened while processing this config directive. */
+    bool has_errors;
+};
 
 /**
  * launch nagbar to indicate errors in the configuration file.
  */
 void start_config_error_nagbar(const char *configpath, bool has_errors);
 
+/**
+ * Releases the memory of all variables in ctx.
+ *
+ */
+void free_variables(struct parser_ctx *ctx);
+
+typedef enum {
+    PARSE_FILE_FAILED = -1,
+    PARSE_FILE_SUCCESS = 0,
+    PARSE_FILE_CONFIG_ERRORS = 1,
+} parse_file_result_t;
+
 /**
  * Parses the given file by first replacing the variables, then calling
  * parse_config and launching i3-nagbar if use_nagbar is true.
@@ -47,4 +103,4 @@ void start_config_error_nagbar(const char *configpath, bool has_errors);
  * parsing.
  *
  */
-bool parse_file(const char *f, bool use_nagbar);
+parse_file_result_t parse_file(struct parser_ctx *ctx, const char *f, IncludedFile *included_file);
diff --git a/include/configuration.h b/include/configuration.h
index eff28e6bc..e5ecb4b62 100644
--- a/include/configuration.h
+++ b/include/configuration.h
@@ -15,6 +15,7 @@
 #include "queue.h"
 #include "i3.h"
 
+typedef struct IncludedFile IncludedFile;
 typedef struct Config Config;
 typedef struct Barconfig Barconfig;
 extern char *current_configpath;
@@ -22,6 +23,7 @@ extern char *current_config;
 extern Config config;
 extern SLIST_HEAD(modes_head, Mode) modes;
 extern TAILQ_HEAD(barconfig_head, Barconfig) barconfigs;
+extern TAILQ_HEAD(includedfiles_head, IncludedFile) included_files;
 
 /**
  * Used during the config file lexing/parsing to keep the state of the lexer
@@ -69,6 +71,18 @@ struct Variable {
     SLIST_ENTRY(Variable) variables;
 };
 
+/**
+ * List entry struct for an included file.
+ *
+ */
+struct IncludedFile {
+    char *path;
+    char *raw_contents;
+    char *variable_replaced_contents;
+
+    TAILQ_ENTRY(IncludedFile) files;
+};
+
 /**
  * The configuration file can contain multiple sets of bindings. Apart from the
  * default set (name == "default"), you can specify other sets and change the
diff --git a/include/data.h b/include/data.h
index 9ea09a8cc..ed0931cec 100644
--- a/include/data.h
+++ b/include/data.h
@@ -15,6 +15,7 @@
 #include <xcb/randr.h>
 #include <pcre.h>
 #include <sys/time.h>
+#include <cairo/cairo.h>
 
 #include "queue.h"
 
@@ -433,6 +434,9 @@ struct Window {
      * for_window. */
     char *role;
 
+    /** WM_CLIENT_MACHINE of the window */
+    char *machine;
+
     /** Flag to force re-rendering the decoration upon changes */
     bool name_x_changed;
 
@@ -487,6 +491,9 @@ struct Window {
     double min_aspect_ratio;
     double max_aspect_ratio;
 
+    /** Window icon, as Cairo surface */
+    cairo_surface_t *icon;
+
     /** The window has a nonrectangular shape. */
     bool shaped;
     /** The window has a nonrectangular input shape. */
@@ -519,6 +526,7 @@ struct Match {
     struct regex *mark;
     struct regex *window_role;
     struct regex *workspace;
+    struct regex *machine;
     xcb_atom_t window_type;
     enum {
         U_DONTCHECK = -1,
@@ -541,6 +549,7 @@ struct Match {
            WM_FLOATING_USER,
            WM_FLOATING } window_mode;
     Con *con_id;
+    bool match_all_windows;
 
     /* Where the window looking for a match should be inserted:
      *
@@ -674,6 +683,11 @@ struct Con {
     /** The format with which the window's name should be displayed. */
     char *title_format;
 
+    /** Whether the window icon should be displayed, and with what padding. -1
+      * means display no window icon (default behavior), 0 means display without
+      * any padding, 1 means display with 1 pixel of padding and so on. */
+    int window_icon_padding;
+
     /* a sticky-group is an identifier which bundles several containers to a
      * group. The contents are shared between all of them, that is they are
      * displayed on whichever of the containers is currently visible */
diff --git a/include/i3-atoms_rest.xmacro.h b/include/i3-atoms_rest.xmacro.h
index 75a5f2300..fa915fd69 100644
--- a/include/i3-atoms_rest.xmacro.h
+++ b/include/i3-atoms_rest.xmacro.h
@@ -3,6 +3,7 @@
 xmacro(_NET_WM_USER_TIME) \
 xmacro(_NET_STARTUP_ID) \
 xmacro(_NET_WORKAREA) \
+xmacro(_NET_WM_ICON) \
 xmacro(WM_PROTOCOLS) \
 xmacro(WM_DELETE_WINDOW) \
 xmacro(UTF8_STRING) \
@@ -15,8 +16,10 @@ xmacro(I3_CONFIG_PATH) \
 xmacro(I3_SYNC) \
 xmacro(I3_SHMLOG_PATH) \
 xmacro(I3_PID) \
+xmacro(I3_LOG_STREAM_SOCKET_PATH) \
 xmacro(I3_FLOATING_WINDOW) \
 xmacro(_NET_REQUEST_FRAME_EXTENTS) \
 xmacro(_NET_FRAME_EXTENTS) \
 xmacro(_MOTIF_WM_HINTS) \
-xmacro(WM_CHANGE_STATE)
+xmacro(WM_CHANGE_STATE) \
+xmacro(MANAGER)
diff --git a/include/i3.h b/include/i3.h
index 2c550fa9c..15ca1d463 100644
--- a/include/i3.h
+++ b/include/i3.h
@@ -39,6 +39,7 @@ extern bool debug_build;
 /** The number of file descriptors passed via socket activation. */
 extern int listen_fds;
 extern int conn_screen;
+extern xcb_atom_t wm_sn;
 /**
  * The EWMH support window that is used to indicate that an EWMH-compliant
  * window manager is present. This window is created when i3 starts and
diff --git a/include/ipc.h b/include/ipc.h
index 0d19daf4d..732fa9b4e 100644
--- a/include/ipc.h
+++ b/include/ipc.h
@@ -80,13 +80,6 @@ void ipc_new_client(EV_P_ struct ev_io *w, int revents);
  */
 ipc_client *ipc_new_client_on_fd(EV_P_ int fd);
 
-/**
- * Creates the UNIX domain socket at the given path, sets it to non-blocking
- * mode, bind()s and listen()s on it.
- *
- */
-int ipc_create_socket(const char *filename);
-
 /**
  * Sends the specified event to all IPC clients which are currently connected
  * and subscribed to this kind of event.
diff --git a/include/libi3.h b/include/libi3.h
index c0b9ddbd3..d98fa1fe5 100644
--- a/include/libi3.h
+++ b/include/libi3.h
@@ -445,18 +445,13 @@ bool font_is_pango(void);
  * specified coordinates (from the top left corner of the leftmost, uppermost
  * glyph) and using the provided gc.
  *
+ * The given cairo surface must refer to the specified X drawable.
+ *
  * Text must be specified as an i3String.
  *
  */
 void draw_text(i3String *text, xcb_drawable_t drawable, xcb_gcontext_t gc,
-               xcb_visualtype_t *visual, int x, int y, int max_width);
-
-/**
- * ASCII version of draw_text to print static strings.
- *
- */
-void draw_text_ascii(const char *text, xcb_drawable_t drawable,
-                     xcb_gcontext_t gc, int x, int y, int max_width);
+               cairo_surface_t *surface, int x, int y, int max_width);
 
 /**
  * Predict the text width in pixels for the given text. Text must be
@@ -571,8 +566,6 @@ typedef struct surface_t {
     /* A classic XCB graphics context. */
     xcb_gcontext_t gc;
 
-    xcb_visualtype_t *visual_type;
-
     int width;
     int height;
 
@@ -618,6 +611,11 @@ color_t draw_util_hex_to_color(const char *color);
  */
 void draw_util_text(i3String *text, surface_t *surface, color_t fg_color, color_t bg_color, int x, int y, int max_width);
 
+/**
+ * Draw the given image using libi3.
+ */
+void draw_util_image(cairo_surface_t *image, surface_t *surface, int x, int y, int width, int height);
+
 /**
  * Draws a filled rectangle.
  * This function is a convenience wrapper and takes care of flushing the
@@ -638,3 +636,46 @@ void draw_util_clear_surface(surface_t *surface, color_t color);
  */
 void draw_util_copy_surface(surface_t *src, surface_t *dest, double src_x, double src_y,
                             double dest_x, double dest_y, double width, double height);
+
+/**
+ * Puts the given socket file descriptor into non-blocking mode or dies if
+ * setting O_NONBLOCK failed. Non-blocking sockets are a good idea for our
+ * IPC model because we should by no means block the window manager.
+ *
+ */
+void set_nonblock(int sockfd);
+
+/**
+ * Creates the UNIX domain socket at the given path, sets it to non-blocking
+ * mode, bind()s and listen()s on it.
+ *
+ * The full path to the socket is stored in the char* that out_socketpath points
+ * to.
+ *
+ */
+int create_socket(const char *filename, char **out_socketpath);
+
+/**
+ * Checks if the given path exists by calling stat().
+ *
+ */
+bool path_exists(const char *path);
+
+/**
+ * Grab a screenshot of the screen's root window and set it as the wallpaper.
+ */
+void set_screenshot_as_wallpaper(xcb_connection_t *conn, xcb_screen_t *screen);
+
+/**
+ * Test whether the screen's root window has a background set.
+ *
+ * This opens & closes a window and test whether the root window still shows the
+ * content of the window.
+ */
+bool is_background_set(xcb_connection_t *conn, xcb_screen_t *screen);
+
+/**
+ * Reports whether str represents the enabled state (1, yes, true, …).
+ *
+ */
+bool boolstr(const char *str);
diff --git a/include/log.h b/include/log.h
index c2758443a..3a52c64d8 100644
--- a/include/log.h
+++ b/include/log.h
@@ -10,6 +10,7 @@
 #pragma once
 
 #include <config.h>
+#include <ev.h>
 
 /* We will include libi3.h which define its own version of LOG, ELOG.
  * We want *our* version, so we undef the libi3 one. */
@@ -31,6 +32,7 @@
 extern char *errorfilename;
 extern char *shmlogname;
 extern int shmlog_size;
+extern char *current_log_stream_socket_path;
 
 /**
  * Initializes logging by creating an error logfile in /tmp (or
@@ -100,3 +102,5 @@ void verboselog(char *fmt, ...)
  * failures. This function is invoked automatically when exiting.
  */
 void purge_zerobyte_logfile(void);
+
+void log_new_client(EV_P_ struct ev_io *w, int revents);
diff --git a/include/shmlog.h b/include/shmlog.h
index 7b7e133a6..a30852e76 100644
--- a/include/shmlog.h
+++ b/include/shmlog.h
@@ -12,10 +12,6 @@
 
 #include <config.h>
 
-#if !defined(__OpenBSD__)
-#include <pthread.h>
-#endif
-
 /* Default shmlog size if not set by user. */
 extern const int default_shmlog_size;
 
@@ -39,11 +35,4 @@ typedef struct i3_shmlog_header {
      * coincidentally be exactly the same as previously). Overflows can happen
      * and don’t matter — clients use an equality check (==). */
     uint32_t wrap_count;
-
-#if !defined(__OpenBSD__)
-    /* pthread condvar which will be broadcasted whenever there is a new
-     * message in the log. i3-dump-log uses this to implement -f (follow, like
-     * tail -f) in an efficient way. */
-    pthread_cond_t condvar;
-#endif
 } i3_shmlog_header;
diff --git a/include/window.h b/include/window.h
index 6673e835f..9759cc4b8 100644
--- a/include/window.h
+++ b/include/window.h
@@ -95,3 +95,15 @@ void window_update_hints(i3Window *win, xcb_get_property_reply_t *prop, bool *ur
  *
  */
 void window_update_motif_hints(i3Window *win, xcb_get_property_reply_t *prop, border_style_t *motif_border_style);
+
+/**
+ * Updates the WM_CLIENT_MACHINE
+ *
+ */
+void window_update_machine(i3Window *win, xcb_get_property_reply_t *prop);
+
+/**
+ * Updates the _NET_WM_ICON
+ *
+ */
+void window_update_icon(i3Window *win, xcb_get_property_reply_t *prop);
diff --git a/libi3/boolstr.c b/libi3/boolstr.c
new file mode 100644
index 000000000..0fa417dd8
--- /dev/null
+++ b/libi3/boolstr.c
@@ -0,0 +1,25 @@
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ */
+#include "libi3.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+/*
+ * Reports whether str represents the enabled state (1, yes, true, …).
+ *
+ */
+bool boolstr(const char *str) {
+    return (strcasecmp(str, "1") == 0 ||
+            strcasecmp(str, "yes") == 0 ||
+            strcasecmp(str, "true") == 0 ||
+            strcasecmp(str, "on") == 0 ||
+            strcasecmp(str, "enable") == 0 ||
+            strcasecmp(str, "active") == 0);
+}
diff --git a/libi3/create_socket.c b/libi3/create_socket.c
new file mode 100644
index 000000000..4b93ff2da
--- /dev/null
+++ b/libi3/create_socket.c
@@ -0,0 +1,70 @@
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ */
+#include "libi3.h"
+
+#include <unistd.h>
+#include <libgen.h>
+#include <err.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+/*
+ * Creates the UNIX domain socket at the given path, sets it to non-blocking
+ * mode, bind()s and listen()s on it.
+ *
+ * The full path to the socket is stored in the char* that out_socketpath points
+ * to.
+ *
+ */
+int create_socket(const char *filename, char **out_socketpath) {
+    char *resolved = resolve_tilde(filename);
+    DLOG("Creating UNIX socket at %s\n", resolved);
+    char *copy = sstrdup(resolved);
+    const char *dir = dirname(copy);
+    if (!path_exists(dir)) {
+        mkdirp(dir, DEFAULT_DIR_MODE);
+    }
+    free(copy);
+
+    /* Unlink the unix domain socket before */
+    unlink(resolved);
+
+    int sockfd = socket(AF_LOCAL, SOCK_STREAM, 0);
+    if (sockfd < 0) {
+        perror("socket()");
+        free(resolved);
+        return -1;
+    }
+
+    (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
+
+    struct sockaddr_un addr;
+    memset(&addr, 0, sizeof(struct sockaddr_un));
+    addr.sun_family = AF_LOCAL;
+    strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
+    if (bind(sockfd, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) {
+        perror("bind()");
+        free(resolved);
+        return -1;
+    }
+
+    set_nonblock(sockfd);
+
+    if (listen(sockfd, 5) < 0) {
+        perror("listen()");
+        free(resolved);
+        return -1;
+    }
+
+    free(*out_socketpath);
+    *out_socketpath = resolved;
+    return sockfd;
+}
diff --git a/libi3/draw_util.c b/libi3/draw_util.c
index 313dc29ac..30eae656e 100644
--- a/libi3/draw_util.c
+++ b/libi3/draw_util.c
@@ -35,19 +35,22 @@ static void draw_util_set_source_color(surface_t *surface, color_t color);
 void draw_util_surface_init(xcb_connection_t *conn, surface_t *surface, xcb_drawable_t drawable,
                             xcb_visualtype_t *visual, int width, int height) {
     surface->id = drawable;
-    surface->visual_type = ((visual == NULL) ? visual_type : visual);
     surface->width = width;
     surface->height = height;
 
+    if (visual == NULL)
+        visual = visual_type;
+
     surface->gc = xcb_generate_id(conn);
     xcb_void_cookie_t gc_cookie = xcb_create_gc_checked(conn, surface->gc, surface->id, 0, NULL);
 
     xcb_generic_error_t *error = xcb_request_check(conn, gc_cookie);
     if (error != NULL) {
         ELOG("Could not create graphical context. Error code: %d. Please report this bug.\n", error->error_code);
+        free(error);
     }
 
-    surface->surface = cairo_xcb_surface_create(conn, surface->id, surface->visual_type, width, height);
+    surface->surface = cairo_xcb_surface_create(conn, surface->id, visual, width, height);
     surface->cr = cairo_create(surface->surface);
 }
 
@@ -56,6 +59,19 @@ void draw_util_surface_init(xcb_connection_t *conn, surface_t *surface, xcb_draw
  *
  */
 void draw_util_surface_free(xcb_connection_t *conn, surface_t *surface) {
+    cairo_status_t status = CAIRO_STATUS_SUCCESS;
+    if (surface->cr) {
+        status = cairo_status(surface->cr);
+    }
+    if (status != CAIRO_STATUS_SUCCESS) {
+        LOG("Found cairo context in an error status while freeing, error %d is %s",
+            status, cairo_status_to_string(status));
+    }
+
+    /* NOTE: This function is also called on uninitialised surface_t instances.
+     * The x11 error from xcb_free_gc(conn, XCB_NONE) is silently ignored
+     * elsewhere.
+     */
     xcb_free_gc(conn, surface->gc);
     cairo_surface_destroy(surface->surface);
     cairo_destroy(surface->cr);
@@ -133,12 +149,36 @@ void draw_util_text(i3String *text, surface_t *surface, color_t fg_color, color_
     CAIRO_SURFACE_FLUSH(surface->surface);
 
     set_font_colors(surface->gc, fg_color, bg_color);
-    draw_text(text, surface->id, surface->gc, surface->visual_type, x, y, max_width);
+    draw_text(text, surface->id, surface->gc, surface->surface, x, y, max_width);
 
     /* Notify cairo that we (possibly) used another way to draw on the surface. */
     cairo_surface_mark_dirty(surface->surface);
 }
 
+/**
+ * Draw the given image using libi3.
+ * This function is a convenience wrapper and takes care of flushing the
+ * surface as well as restoring the cairo state.
+ *
+ */
+void draw_util_image(cairo_surface_t *image, surface_t *surface, int x, int y, int width, int height) {
+    RETURN_UNLESS_SURFACE_INITIALIZED(surface);
+
+    cairo_save(surface->cr);
+
+    cairo_translate(surface->cr, x, y);
+
+    const int src_width = cairo_image_surface_get_width(image);
+    const int src_height = cairo_image_surface_get_height(image);
+    double scale = MIN((double)width / src_width, (double)height / src_height);
+    cairo_scale(surface->cr, scale, scale);
+
+    cairo_set_source_surface(surface->cr, image, 0, 0);
+    cairo_paint(surface->cr);
+
+    cairo_restore(surface->cr);
+}
+
 /*
  * Draws a filled rectangle.
  * This function is a convenience wrapper and takes care of flushing the
diff --git a/libi3/font.c b/libi3/font.c
index 477509d03..4b9d5128d 100644
--- a/libi3/font.c
+++ b/libi3/font.c
@@ -83,12 +83,10 @@ static bool load_pango_font(i3Font *font, const char *desc) {
  *
  */
 static void draw_text_pango(const char *text, size_t text_len,
-                            xcb_drawable_t drawable, xcb_visualtype_t *visual, int x, int y,
-                            int max_width, bool pango_markup) {
+                            xcb_drawable_t drawable, cairo_surface_t *surface,
+                            int x, int y, int max_width, bool pango_markup) {
     /* Create the Pango layout */
     /* root_visual_type is cached in load_pango_font */
-    cairo_surface_t *surface = cairo_xcb_surface_create(conn, drawable,
-                                                        visual, x + max_width, y + savedFont->height);
     cairo_t *cr = cairo_create(surface);
     PangoLayout *layout = create_layout_with_dpi(cr);
     gint height;
@@ -116,7 +114,6 @@ static void draw_text_pango(const char *text, size_t text_len,
     /* Free resources */
     g_object_unref(layout);
     cairo_destroy(cr);
-    cairo_surface_destroy(surface);
 }
 
 /*
@@ -360,11 +357,8 @@ static void draw_text_xcb(const xcb_char2b_t *text, size_t text_len, xcb_drawabl
  *
  */
 void draw_text(i3String *text, xcb_drawable_t drawable, xcb_gcontext_t gc,
-               xcb_visualtype_t *visual, int x, int y, int max_width) {
+               cairo_surface_t *surface, int x, int y, int max_width) {
     assert(savedFont != NULL);
-    if (visual == NULL) {
-        visual = root_visual_type;
-    }
 
     switch (savedFont->type) {
         case FONT_TYPE_NONE:
@@ -377,42 +371,7 @@ void draw_text(i3String *text, xcb_drawable_t drawable, xcb_gcontext_t gc,
         case FONT_TYPE_PANGO:
             /* Render the text using Pango */
             draw_text_pango(i3string_as_utf8(text), i3string_get_num_bytes(text),
-                            drawable, visual, x, y, max_width, i3string_is_markup(text));
-            return;
-    }
-}
-
-/*
- * ASCII version of draw_text to print static strings.
- *
- */
-void draw_text_ascii(const char *text, xcb_drawable_t drawable,
-                     xcb_gcontext_t gc, int x, int y, int max_width) {
-    assert(savedFont != NULL);
-
-    switch (savedFont->type) {
-        case FONT_TYPE_NONE:
-            /* Nothing to do */
-            return;
-        case FONT_TYPE_XCB: {
-            size_t text_len = strlen(text);
-            if (text_len > 255) {
-                /* The text is too long to draw it directly to X */
-                i3String *str = i3string_from_utf8(text);
-                draw_text(str, drawable, gc, NULL, x, y, max_width);
-                i3string_free(str);
-            } else {
-                /* X11 coordinates for fonts start at the baseline */
-                int pos_y = y + savedFont->specific.xcb.info->font_ascent;
-
-                xcb_image_text_8(conn, text_len, drawable, gc, x, pos_y, text);
-            }
-            break;
-        }
-        case FONT_TYPE_PANGO:
-            /* Render the text using Pango */
-            draw_text_pango(text, strlen(text),
-                            drawable, root_visual_type, x, y, max_width, false);
+                            drawable, surface, x, y, max_width, i3string_is_markup(text));
             return;
     }
 }
diff --git a/libi3/get_config_path.c b/libi3/get_config_path.c
index 4909e116b..1f2b4c05a 100644
--- a/libi3/get_config_path.c
+++ b/libi3/get_config_path.c
@@ -11,15 +11,6 @@
 #include <string.h>
 #include <sys/stat.h>
 
-/*
- * Checks if the given path exists by calling stat().
- *
- */
-static bool path_exists(const char *path) {
-    struct stat buf;
-    return (stat(path, &buf) == 0);
-}
-
 /*
  * Get the path of the first configuration file found. If override_configpath is
  * specified, that path is returned and saved for further calls. Otherwise,
diff --git a/libi3/get_process_filename.c b/libi3/get_process_filename.c
index 21429ec36..d29f8db1b 100644
--- a/libi3/get_process_filename.c
+++ b/libi3/get_process_filename.c
@@ -27,15 +27,14 @@ char *get_process_filename(const char *prefix) {
             char *tmp;
             sasprintf(&tmp, "%s/i3", dir);
             dir = tmp;
-            struct stat buf;
-            if (stat(dir, &buf) != 0) {
-                if (mkdir(dir, 0700) == -1) {
-                    warn("Could not mkdir(%s)", dir);
-                    errx(EXIT_FAILURE, "Check permissions of $XDG_RUNTIME_DIR = '%s'",
-                         getenv("XDG_RUNTIME_DIR"));
-                    perror("mkdir()");
-                    return NULL;
-                }
+            /* mkdirp() should prevent race between multiple i3 instances started
+             * in parallel from causing problem */
+            if (mkdirp(dir, 0700) == -1) {
+                warn("Could not mkdirp(%s)", dir);
+                errx(EXIT_FAILURE, "Check permissions of $XDG_RUNTIME_DIR = '%s'",
+                     getenv("XDG_RUNTIME_DIR"));
+                perror("mkdirp()");
+                return NULL;
             }
         } else {
             /* If not, we create a (secure) temp directory using the template
diff --git a/libi3/is_background_set.c b/libi3/is_background_set.c
new file mode 100644
index 000000000..b3b6e6a63
--- /dev/null
+++ b/libi3/is_background_set.c
@@ -0,0 +1,117 @@
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ */
+#include "libi3.h"
+
+#include <xcb/xcb_aux.h>
+
+/**
+ * Find the region in the given window that is not covered by a mapped child
+ * window.
+ */
+static cairo_region_t *unobscured_region(xcb_connection_t *conn, xcb_window_t window,
+                                         uint16_t window_width, uint16_t window_height) {
+    cairo_rectangle_int_t rectangle;
+    cairo_region_t *region;
+
+    rectangle.x = 0;
+    rectangle.y = 0;
+    rectangle.width = window_width;
+    rectangle.height = window_height;
+    region = cairo_region_create_rectangle(&rectangle);
+
+    xcb_query_tree_reply_t *tree = xcb_query_tree_reply(conn, xcb_query_tree_unchecked(conn, window), NULL);
+    if (!tree) {
+        return region;
+    }
+
+    /* Get information about children */
+    uint16_t n_children = tree->children_len;
+    xcb_window_t *children = xcb_query_tree_children(tree);
+
+    xcb_get_geometry_cookie_t geometries[n_children];
+    xcb_get_window_attributes_cookie_t attributes[n_children];
+
+    for (int i = 0; i < n_children; i++) {
+        geometries[i] = xcb_get_geometry_unchecked(conn, children[i]);
+        attributes[i] = xcb_get_window_attributes_unchecked(conn, children[i]);
+    }
+
+    /* Remove every visible child from the region */
+    for (int i = 0; i < n_children; i++) {
+        xcb_get_geometry_reply_t *geom = xcb_get_geometry_reply(conn, geometries[i], NULL);
+        xcb_get_window_attributes_reply_t *attr = xcb_get_window_attributes_reply(conn, attributes[i], NULL);
+
+        if (geom && attr && attr->map_state == XCB_MAP_STATE_VIEWABLE) {
+            rectangle.x = geom->x;
+            rectangle.y = geom->y;
+            rectangle.width = geom->width;
+            rectangle.height = geom->height;
+            cairo_region_subtract_rectangle(region, &rectangle);
+        }
+
+        free(geom);
+        free(attr);
+    }
+
+    free(tree);
+    return region;
+}
+
+static void find_unobscured_pixel(xcb_connection_t *conn, xcb_window_t window,
+                                  uint16_t window_width, uint16_t window_height,
+                                  uint16_t *x, uint16_t *y) {
+    cairo_region_t *region = unobscured_region(conn, window, window_width, window_height);
+    if (cairo_region_num_rectangles(region) > 0) {
+        /* Return the top left pixel of the first rectangle */
+        cairo_rectangle_int_t rect;
+        cairo_region_get_rectangle(region, 0, &rect);
+        *x = rect.x;
+        *y = rect.y;
+    } else {
+        /* No unobscured area found */
+        *x = 0;
+        *y = 0;
+    }
+    cairo_region_destroy(region);
+}
+
+static uint32_t flicker_window_at(xcb_connection_t *conn, xcb_screen_t *screen, int16_t x, int16_t y, xcb_window_t window,
+                                  uint32_t pixel) {
+    xcb_create_window(conn, XCB_COPY_FROM_PARENT, window, screen->root, x, y, 10, 10,
+                      0, XCB_WINDOW_CLASS_INPUT_OUTPUT, XCB_COPY_FROM_PARENT,
+                      XCB_CW_BACK_PIXEL | XCB_CW_OVERRIDE_REDIRECT, (uint32_t[]){pixel, 1});
+    xcb_map_window(conn, window);
+    xcb_clear_area(conn, 0, window, 0, 0, 0, 0);
+    xcb_aux_sync(conn);
+    xcb_destroy_window(conn, window);
+
+    xcb_get_image_reply_t *img = xcb_get_image_reply(conn,
+                                                     xcb_get_image_unchecked(conn, XCB_IMAGE_FORMAT_Z_PIXMAP, screen->root, x, y, 1, 1, ~0),
+                                                     NULL);
+    uint32_t result = 0;
+    if (img) {
+        uint8_t *data = xcb_get_image_data(img);
+        uint8_t depth = img->depth;
+        for (int i = 0; i < MIN(depth, 4); i++) {
+            result = (result << 8) | data[i];
+        }
+        free(img);
+    }
+    return result;
+}
+
+bool is_background_set(xcb_connection_t *conn, xcb_screen_t *screen) {
+    uint16_t x, y;
+    find_unobscured_pixel(conn, screen->root, screen->width_in_pixels, screen->height_in_pixels, &x, &y);
+
+    xcb_window_t window = xcb_generate_id(conn);
+
+    uint32_t pixel1 = flicker_window_at(conn, screen, x, y, window, screen->black_pixel);
+    uint32_t pixel2 = flicker_window_at(conn, screen, x, y, window, screen->white_pixel);
+    return pixel1 == pixel2;
+}
diff --git a/libi3/nonblock.c b/libi3/nonblock.c
new file mode 100644
index 000000000..987c274a2
--- /dev/null
+++ b/libi3/nonblock.c
@@ -0,0 +1,21 @@
+#include "libi3.h"
+
+#include <err.h>
+#include <fcntl.h>
+
+/*
+ * Puts the given socket file descriptor into non-blocking mode or dies if
+ * setting O_NONBLOCK failed. Non-blocking sockets are a good idea for our
+ * IPC model because we should by no means block the window manager.
+ *
+ */
+void set_nonblock(int sockfd) {
+    int flags = fcntl(sockfd, F_GETFL, 0);
+    if (flags & O_NONBLOCK) {
+        return;
+    }
+    flags |= O_NONBLOCK;
+    if (fcntl(sockfd, F_SETFL, flags) < 0) {
+        err(-1, "Could not set O_NONBLOCK");
+    }
+}
diff --git a/libi3/path_exists.c b/libi3/path_exists.c
new file mode 100644
index 000000000..5451c3bdd
--- /dev/null
+++ b/libi3/path_exists.c
@@ -0,0 +1,21 @@
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ */
+#include "libi3.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+/*
+ * Checks if the given path exists by calling stat().
+ *
+ */
+bool path_exists(const char *path) {
+    struct stat buf;
+    return (stat(path, &buf) == 0);
+}
diff --git a/libi3/screenshot_wallpaper.c b/libi3/screenshot_wallpaper.c
new file mode 100644
index 000000000..2c115a9e1
--- /dev/null
+++ b/libi3/screenshot_wallpaper.c
@@ -0,0 +1,27 @@
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ */
+#include "libi3.h"
+
+void set_screenshot_as_wallpaper(xcb_connection_t *conn, xcb_screen_t *screen) {
+    uint16_t width = screen->width_in_pixels;
+    uint16_t height = screen->height_in_pixels;
+    xcb_pixmap_t pixmap = xcb_generate_id(conn);
+    xcb_gcontext_t gc = xcb_generate_id(conn);
+
+    xcb_create_pixmap(conn, screen->root_depth, pixmap, screen->root, width, height);
+
+    xcb_create_gc(conn, gc, screen->root,
+                  XCB_GC_FUNCTION | XCB_GC_PLANE_MASK | XCB_GC_FILL_STYLE | XCB_GC_SUBWINDOW_MODE,
+                  (uint32_t[]){XCB_GX_COPY, ~0, XCB_FILL_STYLE_SOLID, XCB_SUBWINDOW_MODE_INCLUDE_INFERIORS});
+
+    xcb_copy_area(conn, screen->root, pixmap, gc, 0, 0, 0, 0, width, height);
+    xcb_change_window_attributes(conn, screen->root, XCB_CW_BACK_PIXMAP, (uint32_t[]){pixmap});
+    xcb_free_gc(conn, gc);
+    xcb_free_pixmap(conn, pixmap);
+    xcb_flush(conn);
+}
diff --git a/logo.svg b/logo.svg
index bb3e59817..6f87d0c53 100644
--- a/logo.svg
+++ b/logo.svg
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!-- Created with Inkscape (http://www.inkscape.org/) -->
 <svg
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:cc="http://creativecommons.org/ns#"
@@ -13,9 +12,10 @@
    height="297mm"
    id="svg2"
    sodipodi:version="0.32"
-   inkscape:version="0.46"
-   sodipodi:docname="logo_i3_linuxfr_bapt_v2.svg"
-   inkscape:output_extension="org.inkscape.output.svg.inkscape">
+   inkscape:version="1.0.1 (c497b03c, 2020-09-10)"
+   sodipodi:docname="logo.svg"
+   inkscape:output_extension="org.inkscape.output.svg.inkscape"
+   version="1.1">
   <defs
      id="defs4">
     <linearGradient
@@ -39,10 +39,10 @@
     </linearGradient>
     <inkscape:perspective
        id="perspective3661"
-       inkscape:persp3d-origin="750.50629 : 505.26732 : 1"
-       inkscape:vp_z="683.5728 : 1230.5721 : 1"
-       inkscape:vp_y="0 : 1946.8917 : 0"
-       inkscape:vp_x="-526.84957 : 2.2065866e-13 : 0"
+       inkscape:persp3d-origin="800.54004 : 538.95181 : 1"
+       inkscape:vp_z="729.14432 : 1312.6102 : 1"
+       inkscape:vp_y="0 : 2076.6845 : 0"
+       inkscape:vp_x="-561.97287 : 2.3536924e-13 : 0"
        sodipodi:type="inkscape:persp3d" />
     <linearGradient
        id="linearGradient3284">
@@ -112,10 +112,10 @@
     </linearGradient>
     <inkscape:perspective
        sodipodi:type="inkscape:persp3d"
-       inkscape:vp_x="-526.84957 : 2.9848654e-13 : 0"
-       inkscape:vp_y="1.192088e-13 : 1946.8917 : 0"
-       inkscape:vp_z="680.54236 : 1232.3792 : 1"
-       inkscape:persp3d-origin="730.30325 : 937.39936 : 1"
+       inkscape:vp_x="-561.97287 : 3.1838564e-13 : 0"
+       inkscape:vp_y="1.2715605e-13 : 2076.6845 : 0"
+       inkscape:vp_z="725.91185 : 1314.5378 : 1"
+       inkscape:persp3d-origin="778.99013 : 999.89265 : 1"
        id="perspective10" />
     <radialGradient
        inkscape:collect="always"
@@ -152,10 +152,10 @@
        gradientUnits="userSpaceOnUse" />
     <inkscape:perspective
        id="perspective3373"
-       inkscape:persp3d-origin="372.04724 : 350.78739 : 1"
-       inkscape:vp_z="744.09448 : 526.18109 : 1"
-       inkscape:vp_y="0 : 1000 : 0"
-       inkscape:vp_x="0 : 526.18109 : 1"
+       inkscape:persp3d-origin="396.85039 : 374.17322 : 1"
+       inkscape:vp_z="793.70078 : 561.25983 : 1"
+       inkscape:vp_y="0 : 1066.6667 : 0"
+       inkscape:vp_x="0 : 561.25983 : 1"
        sodipodi:type="inkscape:persp3d" />
     <linearGradient
        id="linearGradient3211">
@@ -282,15 +282,17 @@
      inkscape:pageopacity="0.0"
      inkscape:pageshadow="2"
      inkscape:zoom="1"
-     inkscape:cx="239.17981"
-     inkscape:cy="807.75327"
+     inkscape:cx="164.67981"
+     inkscape:cy="285.75327"
      inkscape:document-units="px"
      inkscape:current-layer="layer1"
      showgrid="false"
      inkscape:window-width="1272"
-     inkscape:window-height="950"
+     inkscape:window-height="856"
      inkscape:window-x="24"
-     inkscape:window-y="24" />
+     inkscape:window-y="22"
+     inkscape:document-rotation="0"
+     inkscape:window-maximized="0" />
   <metadata
      id="metadata7">
     <rdf:RDF>
@@ -495,7 +497,7 @@
     <path
        style="fill:none;fill-opacity:1;fill-rule:nonzero;stroke:#000000;stroke-width:1;stroke-linecap:round;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dashoffset:0;stroke-opacity:1;display:inline"
        d="M 182.85714,106.6479 L 182.85714,415.21935 L 182.85714,106.6479 z"
-       id="rect3246"
+       id="path934"
        sodipodi:nodetypes="ccc" />
     <path
        sodipodi:nodetypes="ccc"
@@ -515,7 +517,7 @@
      style="display:inline">
     <path
        style="fill:#ffffff;fill-opacity:1;fill-rule:evenodd;stroke:none;stroke-width:60;stroke-linecap:round;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:none;stroke-opacity:1;display:inline;opacity:0.87;color:#000000;marker:none;marker-start:none;marker-mid:none;marker-end:none;stroke-dashoffset:0;visibility:visible;overflow:visible;enable-background:accumulate"
-       d="M 232.58675,170.48705 C 227.06049,176.20076 227.20767,185.31117 232.91561,190.84339 C 232.91561,190.84339 262.59553,220.39981 299.69461,257.34451 C 307.623,265.23991 308.90149,274.72214 304.93625,288.45787 C 300.97101,302.19359 290.70796,318.30838 277.52977,331.54163 C 264.35159,344.77488 248.27973,355.10504 234.56067,359.12752 C 220.8416,363.15 211.35411,361.91106 203.42572,354.01566 C 184.92972,335.59662 168.41707,318.85373 156.40736,306.74834 C 150.40251,300.69564 145.54261,295.80887 142.03518,292.37245 C 140.28147,290.65424 138.89319,289.33126 137.69845,288.24431 C 137.10109,287.70084 136.61259,287.25572 135.77496,286.60406 C 135.35615,286.27823 134.96551,285.91185 133.67159,285.18696 C 133.02464,284.82451 132.24966,284.30398 130.06183,283.75178 C 127.87401,283.19957 121.6694,282.14423 116.27918,287.55701 C 113.07203,290.69556 111.51088,295.14955 112.05678,299.60357 C 112.60268,304.05759 115.19327,308.00272 119.06345,310.27384 C 119.7757,310.94033 120.58858,311.68637 121.88019,312.95183 C 125.15148,316.1569 129.98569,321.01459 135.96535,327.0419 C 147.92468,339.09652 164.49757,355.90001 183.10064,374.42567 C 199.28665,390.54432 222.47127,392.68834 242.66987,386.76604 C 262.86847,380.84373 281.97067,367.90254 297.93978,351.86671 C 313.90889,335.83087 326.77031,316.67487 332.60834,296.45175 C 338.44637,276.22863 336.20569,253.05315 320.01968,236.9345 C 282.92061,199.9898 253.24069,170.43338 253.24069,170.43338 C 250.52156,167.6512 246.79264,166.08723 242.90239,166.09734 C 239.01212,166.10745 235.29138,167.69077 232.58675,170.48705 L 232.58675,170.48705 z"
+       d="m 232.58675,170.48705 c -5.52626,5.71371 -5.37908,14.82412 0.32886,20.35634 0,0 29.67992,29.55642 66.779,66.50112 7.92839,7.8954 9.20688,17.37763 5.24164,31.11336 -3.96524,13.73572 -14.22829,29.85051 -27.40648,43.08376 -13.17818,13.23325 -29.25004,23.56341 -42.9691,27.58589 -13.71907,4.02248 -23.20656,2.78354 -31.13495,-5.11186 -18.496,-18.41904 -35.00865,-35.16193 -47.01836,-47.26732 -6.00485,-6.0527 -10.86475,-10.93947 -14.37218,-14.37589 -1.75371,-1.71821 -3.14199,-3.04119 -4.33673,-4.12814 -0.59736,-0.54347 -1.08586,-0.98859 -1.92349,-1.64025 -0.41881,-0.32583 -0.80945,-0.69221 -2.10337,-1.4171 -0.64695,-0.36245 -1.42193,-0.88298 -3.60976,-1.43518 -2.18782,-0.55221 -8.39243,-1.60755 -13.78265,3.80523 -3.20715,3.13855 -4.7683,7.59254 -4.2224,12.04656 0.5459,4.45402 3.90276,7.82444 7.00667,10.67027 0.71225,0.66649 1.52513,1.41253 2.81674,2.67799 3.27129,3.20507 8.1055,8.06276 14.08516,14.09007 11.95933,12.05462 28.53222,28.85811 47.13529,47.38377 16.18601,16.11865 39.37063,18.26267 59.56923,12.34037 20.1986,-5.92231 39.3008,-18.8635 55.26991,-34.89933 15.96911,-16.03584 28.83053,-35.19184 34.66856,-55.41496 5.83803,-20.22312 3.59735,-43.3986 -12.58866,-59.51725 l -66.77899,-66.50112 c -2.71913,-2.78218 -6.44805,-4.34615 -10.3383,-4.33604 -3.89027,0.0101 -7.61101,1.59343 -10.31564,4.38971 zm 232.58675,170.48705 c -5.52626,5.71371 -5.37908,14.82412 0.32886,20.35634 0,0 29.67992,29.55642 66.779,66.50112 7.92839,7.8954 9.20688,17.37763 5.24164,31.11336 -3.96524,13.73572 -14.22829,29.85051 -27.40648,43.08376 -13.17818,13.23325 -29.25004,23.56341 -42.9691,27.58589 -13.71907,4.02248 -23.20656,2.78354 -31.13495,-5.11186 -18.496,-18.41904 -35.00865,-35.16193 -47.01836,-47.26732 -6.00485,-6.0527 -10.86475,-10.93947 -14.37218,-14.37589 -1.75371,-1.71821 -3.14199,-3.04119 -4.33673,-4.12814 -0.59736,-0.54347 -1.08586,-0.98859 -1.92349,-1.64025 -0.41881,-0.32583 -0.80945,-0.69221 -2.10337,-1.4171 -0.64695,-0.36245 -1.42193,-0.88298 -3.60976,-1.43518 -2.18782,-0.55221 -8.39243,-1.60755 -13.78265,3.80523 -3.20715,3.13855 -4.7683,7.59254 -4.2224,12.04656 0.5459,4.45402 3.90276,7.82444 7.00667,10.67027 0.71225,0.66649 1.52513,1.41253 2.81674,2.67799 3.27129,3.20507 8.1055,8.06276 14.08516,14.09007 11.95933,12.05462 28.53222,28.85811 47.13529,47.38377 16.18601,16.11865 39.37063,18.26267 59.56923,12.34037 20.1986,-5.92231 39.3008,-18.8635 55.26991,-34.89933 15.96911,-16.03584 28.83053,-35.19184 34.66856,-55.41496 5.83803,-20.22312 3.59735,-43.3986 -12.58866,-59.51725 l -66.77899,-66.50112 c -2.71913,-2.78218 -6.44805,-4.34615 -10.3383,-4.33604 -3.89027,0.0101 -7.61101,1.59343 -10.31564,4.38971 z"
        id="path2405" />
     <path
        style="fill:#ffffff;fill-opacity:1;fill-rule:evenodd;stroke:none;stroke-width:60;stroke-linecap:round;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:none;stroke-opacity:1;display:inline;opacity:0.87"
diff --git a/man/i3-msg.man b/man/i3-msg.man
index ce9b476d5..97013fa51 100644
--- a/man/i3-msg.man
+++ b/man/i3-msg.man
@@ -9,7 +9,7 @@ i3-msg - send messages to i3 window manager
 
 == SYNOPSIS
 
-i3-msg  [-q] [-v] [-h] [-s socket] [-t type] [message]
+i3-msg  [-q] [-v] [-h] [-s socket] [-t type] [-r] [message]
 
 == OPTIONS
 
@@ -36,6 +36,10 @@ Instead of exiting right after receiving the first subscribed event,
 wait indefinitely for all of them. Can only be used with "-t subscribe".
 See the "subscribe" IPC message type below for details.
 
+*-q, --raw*::
+Display the raw JSON reply instead of pretty-printing errors (for commands) or
+displaying the top-level config file contents (for GET_CONFIG).
+
 *message*::
 Send ipc message, see below.
 
diff --git a/man/i3-nagbar.man b/man/i3-nagbar.man
index ef3a35458..55696dff3 100644
--- a/man/i3-nagbar.man
+++ b/man/i3-nagbar.man
@@ -9,7 +9,7 @@ i3-nagbar - displays an error bar on top of your screen
 
 == SYNOPSIS
 
-i3-nagbar [-m <message>] [-b <button> <action>] [-B <button> <action>] [-t warning|error] [-f <font>] [-v]
+i3-nagbar [-m <message>] [-b <button> <action>] [-B <button> <action>] [-t warning|error] [-f <font>] [-v] [-p]
 
 == OPTIONS
 
@@ -39,6 +39,10 @@ i3-sensible-terminal.
 Same as above, but will execute the shell commands directly, without launching a
 terminal emulator.
 
+*-p, --primary*::
+Always opens the i3-nagbar on the primary monitor. By default it opens on the
+focused monitor.
+
 == DESCRIPTION
 
 i3-nagbar is used by i3 to tell you about errors in your configuration file
diff --git a/man/i3-sensible-terminal.man b/man/i3-sensible-terminal.man
index bda5a7239..1b83e07bf 100644
--- a/man/i3-sensible-terminal.man
+++ b/man/i3-sensible-terminal.man
@@ -23,20 +23,20 @@ It tries to start one of the following (in that order):
 
 * $TERMINAL (this is a non-standard variable)
 * x-terminal-emulator (only present on Debian and derivatives)
+* mate-terminal
+* gnome-terminal
+* terminator
+* xfce4-terminal
 * urxvt
 * rxvt
 * termit
-* terminator
 * Eterm
 * aterm
 * uxterm
 * xterm
-* gnome-terminal
 * roxterm
-* xfce4-terminal
 * termite
 * lxterminal
-* mate-terminal
 * terminology
 * st
 * qterminal
diff --git a/man/i3.man b/man/i3.man
index 8157ac779..1974f0b9a 100644
--- a/man/i3.man
+++ b/man/i3.man
@@ -44,6 +44,9 @@ Retrieve the i3 IPC socket path from X11, print it, then exit.
 Limits the size of the i3 SHM log to <limit> bytes. Setting this to 0 disables
 SHM logging entirely. The default is 0 bytes.
 
+--replace::
+Replace an existing window manager.
+
 == DESCRIPTION
 
 === INTRODUCTION
diff --git a/man/i3bar.man b/man/i3bar.man
index d0b0148c7..479e10fcb 100644
--- a/man/i3bar.man
+++ b/man/i3bar.man
@@ -9,7 +9,7 @@ i3bar - xcb-based status- and workspace-bar
 
 == SYNOPSIS
 
-*i3bar* [*-s* 'sock_path'] [*-b* 'bar_id'] [*-v*] [*-h*]
+*i3bar* [*-b* 'bar_id'] [*-s* 'sock_path'] [*-t*] [*-h*] [*-v*] [*-V*]
 
 == WARNING
 
@@ -25,14 +25,21 @@ You have been warned!
 Overwrites the path to the i3 IPC socket.
 
 *-b, --bar_id* 'bar_id'::
-Specifies the bar ID for which to get the configuration from i3.
+Specifies the bar ID for which to get the configuration from i3. By default,
+i3bar will use the first bar block as configured in i3.
 
-*-v, --version*::
-Display version number and exit.
+*-t, --transparency*::
+Enable transparency (RGBA colors)
 
 *-h, --help*::
 Display a short help-message and exit
 
+*-v, --version*::
+Display version number and exit.
+
+*-V*::
+Be verbose.
+
 == DESCRIPTION
 
 *i3bar* displays a bar at the bottom (or top) of your monitor(s) containing
diff --git a/meson.build b/meson.build
index b052efa45..eb02f369e 100644
--- a/meson.build
+++ b/meson.build
@@ -6,7 +6,7 @@
 project(
   'i3',
   'c',
-    version: '4.19.1',
+  version: '4.20',
   default_options: [
     'c_std=c11',
     'warning_level=1',  # enable all warnings (-Wall)
@@ -63,7 +63,7 @@ config_h = declare_dependency(
   sources: vcs_tag(
     input: config_h_in,
     output: 'config.h',
-    fallback: meson.project_version() + ' (2021-02-01)',
+    fallback: meson.project_version() + ' (2021-10-19)',
   )
 )
 
@@ -325,6 +325,8 @@ ev_dep = cc.find_library('ev')
 inc = include_directories('include')
 
 libi3srcs = [
+  'libi3/boolstr.c',
+  'libi3/create_socket.c',
   'libi3/dpi.c',
   'libi3/draw_util.c',
   'libi3/fake_configure_notify.c',
@@ -341,11 +343,15 @@ libi3srcs = [
   'libi3/ipc_recv_message.c',
   'libi3/ipc_send_message.c',
   'libi3/is_debug_build.c',
+  'libi3/path_exists.c',
   'libi3/resolve_tilde.c',
   'libi3/root_atom_contents.c',
   'libi3/safewrappers.c',
   'libi3/string.c',
   'libi3/ucs2_conversion.c',
+  'libi3/nonblock.c',
+  'libi3/screenshot_wallpaper.c',
+  'libi3/is_background_set.c',
 ]
 
 if not cdata.get('HAVE_STRNDUP')
@@ -514,6 +520,7 @@ executable(
     'i3-config-wizard/i3-config-wizard-atoms.xmacro.h',
     'i3-config-wizard/main.c',
     'i3-config-wizard/xcb.h',
+    config_parser,
   ],
   install: true,
   include_directories: include_directories('include', 'i3-config-wizard'),
@@ -642,7 +649,7 @@ if get_option('docs')
       '@OUTPUT@',
     ],
     install: true,
-    install_dir: join_paths(get_option('datadir'), 'doc', 'i3'),
+    install_dir: docdir,
   )
 
   custom_target(
@@ -655,7 +662,7 @@ if get_option('docs')
       '@OUTPUT@',
     ],
     install: true,
-    install_dir: join_paths(get_option('datadir'), 'doc', 'i3'),
+    install_dir: docdir,
   )
 endif
 
@@ -669,7 +676,10 @@ executable(
 
 executable(
   'test.commands_parser',
-  'src/commands_parser.c',
+  [
+    'src/commands_parser.c',
+    command_parser,
+  ],
   include_directories: inc,
   c_args: '-DTEST_PARSER',
   dependencies: common_deps,
@@ -678,7 +688,10 @@ executable(
 
 executable(
   'test.config_parser',
-  'src/config_parser.c',
+  [
+    'src/config_parser.c',
+    config_parser,
+  ],
   include_directories: inc,
   c_args: '-DTEST_PARSER',
   dependencies: common_deps,
@@ -706,6 +719,7 @@ if meson.version().version_compare('>=0.46.0')
       anyevent_i3,
       i3test_pm,
     ],
+    timeout: 120,  # Default of 30 seconds can cause timeouts on slower machines
   )
 else
   # meson < 0.46.0 does not support the depends arg in test targets.
diff --git a/parser-specs/commands.spec b/parser-specs/commands.spec
index 20de3e442..d53945d4c 100644
--- a/parser-specs/commands.spec
+++ b/parser-specs/commands.spec
@@ -40,6 +40,7 @@ state INITIAL:
   'scratchpad' -> SCRATCHPAD
   'swap' -> SWAP
   'title_format' -> TITLE_FORMAT
+  'title_window_icon' -> TITLE_WINDOW_ICON
   'mode' -> MODE
   'bar' -> BAR
   'gaps' -> GAPS
@@ -55,7 +56,8 @@ state CRITERIA:
   ctype = 'title'       -> CRITERION
   ctype = 'urgent'      -> CRITERION
   ctype = 'workspace'   -> CRITERION
-  ctype = 'tiling', 'floating'
+  ctype = 'machine'     -> CRITERION
+  ctype = 'tiling', 'floating', 'all'
       -> call cmd_criteria_add($ctype, NULL); CRITERIA
   ']' -> call cmd_criteria_match_windows(); INITIAL
 
@@ -402,8 +404,10 @@ state MOVE_WORKSPACE_NUMBER:
       -> call cmd_move_con_to_workspace_number($number, $no_auto_back_and_forth)
 
 state MOVE_TO_OUTPUT:
-  output = string
-      -> call cmd_move_con_to_output($output)
+  output = word
+      -> call cmd_move_con_to_output($output, 0); MOVE_TO_OUTPUT
+  end
+      -> call cmd_move_con_to_output(NULL, 0); INITIAL
 
 state MOVE_TO_MARK:
   mark = string
@@ -411,9 +415,13 @@ state MOVE_TO_MARK:
 
 state MOVE_WORKSPACE_TO_OUTPUT:
   'output'
-      ->
-  output = string
-      -> call cmd_move_workspace_to_output($output)
+      -> MOVE_WORKSPACE_TO_OUTPUT_WORD
+
+state MOVE_WORKSPACE_TO_OUTPUT_WORD:
+  output = word
+      -> call cmd_move_con_to_output($output, 1); MOVE_WORKSPACE_TO_OUTPUT_WORD
+  end
+      -> call cmd_move_con_to_output(NULL, 1); INITIAL
 
 state MOVE_TO_ABSOLUTE_POSITION:
   'position'
@@ -473,6 +481,20 @@ state TITLE_FORMAT:
   format = string
       -> call cmd_title_format($format)
 
+state TITLE_WINDOW_ICON:
+  'padding'
+    -> TITLE_WINDOW_ICON_PADDING
+  enable = '1', 'yes', 'true', 'on', 'enable', 'active', '0', 'no', 'false', 'off', 'disable', 'inactive'
+    -> call cmd_title_window_icon($enable, 0)
+
+state TITLE_WINDOW_ICON_PADDING:
+  end
+    -> call cmd_title_window_icon($enable, &padding)
+  'px'
+    -> call cmd_title_window_icon($enable, &padding)
+  padding = number
+    ->
+
 # bar (hidden_state hide|show|toggle)|(mode dock|hide|invisible|toggle) [<bar_id>]
 state BAR:
   'hidden_state'
diff --git a/parser-specs/config.spec b/parser-specs/config.spec
index 9f06406e4..2bd3434ef 100644
--- a/parser-specs/config.spec
+++ b/parser-specs/config.spec
@@ -20,6 +20,7 @@ state INITIAL:
   'set '                                   -> IGNORE_LINE
   'set	'                                  -> IGNORE_LINE
   'set_from_resource'                      -> IGNORE_LINE
+  'include'                                -> INCLUDE
   bindtype = 'bindsym', 'bindcode', 'bind' -> BINDING
   'bar'                                    -> BARBRACE
   'font'                                   -> FONT
@@ -90,6 +91,11 @@ state SMART_GAPS:
   enabled = 'inverse_outer'
       -> call cfg_smart_gaps($enabled)
 
+# include <pattern>
+state INCLUDE:
+  pattern = string
+      -> call cfg_include($pattern)
+
 # floating_minimum_size <width> x <height>
 state FLOATING_MINIMUM_SIZE_WIDTH:
   width = number
@@ -218,9 +224,10 @@ state CRITERIA:
   ctype = 'title'         -> CRITERION
   ctype = 'urgent'        -> CRITERION
   ctype = 'workspace'     -> CRITERION
+  ctype = 'machine'     -> CRITERION
   ctype = 'floating_from' -> CRITERION_FROM
   ctype = 'tiling_from'   -> CRITERION_FROM
-  ctype = 'tiling', 'floating'
+  ctype = 'tiling', 'floating', 'all'
       -> call cfg_criteria_add($ctype, NULL); CRITERIA
   ']'
       -> call cfg_criteria_pop_state()
@@ -423,6 +430,8 @@ state BINDCOMMAND:
       ->
   command = string
       -> call cfg_binding($bindtype, $modifiers, $key, $release, $border, $whole_window, $exclude_titlebar, $command)
+  end
+      -> call cfg_binding($bindtype, $modifiers, $key, $release, $border, $whole_window, $exclude_titlebar, $command)
 
 ################################################################################
 # Mode configuration
diff --git a/release.sh b/release.sh
index c6b045c0a..134423734 100755
--- a/release.sh
+++ b/release.sh
@@ -1,8 +1,10 @@
 #!/bin/zsh
 # This script is used to prepare a new release of i3.
 
+set -eu
+
 export RELEASE_VERSION="4.19"
-export PREVIOUS_VERSION="4.18"
+export PREVIOUS_VERSION="4.18.3"
 export RELEASE_BRANCH="next"
 
 if [ ! -e "../i3.github.io" ]
@@ -24,12 +26,6 @@ then
 	exit 1
 fi
 
-if git diff-files --quiet --exit-code debian/changelog
-then
-	echo "Expected debian/changelog to be changed (containing the changelog for ${RELEASE_VERSION})."
-	exit 1
-fi
-
 eval $(gpg-agent --daemon)
 export GPG_AGENT_INFO
 
@@ -52,28 +48,32 @@ if [ ! -e "${STARTDIR}/RELEASE-NOTES-${RELEASE_VERSION}" ]; then
 	exit 1
 fi
 git checkout -b release-${RELEASE_VERSION}
+git rm RELEASE-NOTES-*
 cp "${STARTDIR}/RELEASE-NOTES-${RELEASE_VERSION}" "RELEASE-NOTES-${RELEASE_VERSION}"
 git add RELEASE-NOTES-${RELEASE_VERSION}
-git rm RELEASE-NOTES-${PREVIOUS_VERSION}
-sed -i "s/^\s*version: '${PREVIOUS_VERSION}'/    version: '${RELEASE_VERSION}'/" meson.build
+# Update the release version:
+sed -i "s/^\s*version: '4.[^']*'/  version: '${RELEASE_VERSION}'/" meson.build
+cp meson.build "${TMPDIR}/meson.build"
+# Inject the release date into meson.build for the dist tarball:
+sed -i "s/'-non-git'/' ($(date +'%Y-%m-%d'))'/" meson.build
 git commit -a -m "release i3 ${RELEASE_VERSION}"
 git tag "${RELEASE_VERSION}" -m "release i3 ${RELEASE_VERSION}" --sign --local-user=0x4AC8EE1D
 
 mkdir build
 (cd build && meson .. && ninja dist)
-cp build/meson-build/i3-${RELEASE_VERSION}.tar.xz .
+cp build/meson-dist/i3-${RELEASE_VERSION}.tar.xz .
 
 echo "Differences in the release tarball file lists:"
 
 diff --color -u \
-	<(tar tf ../i3-${PREVIOUS_VERSION}.tar.xz | sed "s,i3-${PREVIOUS_VERSION}/,,g" | sort) \
-	<(tar tf    i3-${RELEASE_VERSION}.tar.xz  | sed "s,i3-${RELEASE_VERSION}/,,g"  | sort)
+	<(tar tf ../i3-${PREVIOUS_VERSION}.tar.* | sed "s,i3-${PREVIOUS_VERSION}/,,g" | sort) \
+	<(tar tf    i3-${RELEASE_VERSION}.tar.xz  | sed "s,i3-${RELEASE_VERSION}/,,g"  | sort) || true
 
 gpg --armor -b i3-${RELEASE_VERSION}.tar.xz
 
-echo "${RELEASE_VERSION}-non-git" > I3_VERSION
-git add I3_VERSION
-git commit -a -m "Set non-git version to ${RELEASE_VERSION}-non-git."
+mv "${TMPDIR}/meson.build" .
+git add meson.build
+git commit -a -m "Restore non-git version suffix"
 
 if [ "${RELEASE_BRANCH}" = "stable" ]; then
 	git checkout stable
@@ -94,17 +94,12 @@ git config --add remote.origin.push "+refs/heads/next:refs/heads/next"
 git config --add remote.origin.push "+refs/heads/stable:refs/heads/stable"
 
 ################################################################################
-# Section 2: Debian packaging
+# Section 2: Debian packaging (for QA)
 ################################################################################
 
 cd "${TMPDIR}"
 mkdir debian
 
-# Copy over the changelog because we expect it to be locally modified in the
-# start directory.
-cp "${STARTDIR}/debian/changelog" i3/debian/changelog
-(cd i3 && git add debian/changelog && git commit -m 'Update debian/changelog')
-
 cat > ${TMPDIR}/Dockerfile <<EOT
 FROM debian:sid
 RUN sed -i 's,^deb \(.*\),deb \1\ndeb-src \1,g' /etc/apt/sources.list
@@ -133,9 +128,6 @@ done
 echo "Content of resulting package’s .changes file:"
 cat ${TMPDIR}/debian/*.changes
 
-# debsign is in devscripts, which is available in fedora and debian
-debsign --no-re-sign -k4AC8EE1D ${TMPDIR}/debian/*.changes
-
 # TODO: docker cleanup
 
 ################################################################################
@@ -176,7 +168,7 @@ sed -i "s,Verify you are using i3 ≥ .*,Verify you are using i3 ≥ ${RELEASE_V
 
 (cd _docs && make)
 
-for i in $(find _docs -maxdepth 1 -and -type f -and \! -regex ".*\.\(html\|man\)$" -and \! -name "Makefile")
+for i in $(find _docs -maxdepth 1 -and -type f -and \! -regex ".*\.\(html\|man\|css\)$" -and \! -name "Makefile")
 do
 	base="$(basename $i)"
 	[ -e "${TMPDIR}/i3/docs/${base}" ] && cp "_docs/${base}.html" docs/
@@ -234,6 +226,6 @@ echo "  Create milestone for the next major version with unset due date"
 echo ""
 echo "Announce on:"
 echo "  twitter"
-echo "  google+"
 echo "  #i3 topic"
-echo "  reddit /r/i3wm"
+echo "  reddit /r/i3wm (link post to changelog)"
+echo "  GitHub Discussions → Announcements"
diff --git a/src/bindings.c b/src/bindings.c
index d6255e735..0aa960d31 100644
--- a/src/bindings.c
+++ b/src/bindings.c
@@ -717,6 +717,40 @@ void reorder_bindings(void) {
     }
 }
 
+/*
+ * Returns true if a is a key binding for the same key as b.
+ *
+ */
+static bool binding_same_key(Binding *a, Binding *b) {
+    /* Check if the input types are different */
+    if (a->input_type != b->input_type) {
+        return false;
+    }
+
+    /* Check if one is using keysym while the other is using bindsym. */
+    if ((a->symbol == NULL && b->symbol != NULL) ||
+        (a->symbol != NULL && b->symbol == NULL)) {
+        return false;
+    }
+
+    /* If a is NULL, b has to be NULL, too (see previous conditional).
+     * If the keycodes differ, it can't be a duplicate. */
+    if (a->symbol != NULL &&
+        strcasecmp(a->symbol, b->symbol) != 0) {
+        return false;
+    }
+
+    /* Check if the keycodes or modifiers are different. If so, they
+     * can't be duplicate */
+    if (a->keycode != b->keycode ||
+        a->event_state_mask != b->event_state_mask ||
+        a->release != b->release) {
+        return false;
+    }
+
+    return true;
+}
+
 /*
  * Checks for duplicate key bindings (the same keycode or keysym is configured
  * more than once). If a duplicate binding is found, a message is printed to
@@ -730,31 +764,13 @@ void check_for_duplicate_bindings(struct context *context) {
         TAILQ_FOREACH (bind, bindings, bindings) {
             /* Abort when we reach the current keybinding, only check the
              * bindings before */
-            if (bind == current)
+            if (bind == current) {
                 break;
+            }
 
-            /* Check if the input types are different */
-            if (bind->input_type != current->input_type)
-                continue;
-
-            /* Check if one is using keysym while the other is using bindsym.
-             * If so, skip. */
-            if ((bind->symbol == NULL && current->symbol != NULL) ||
-                (bind->symbol != NULL && current->symbol == NULL))
-                continue;
-
-            /* If bind is NULL, current has to be NULL, too (see above).
-             * If the keycodes differ, it can't be a duplicate. */
-            if (bind->symbol != NULL &&
-                strcasecmp(bind->symbol, current->symbol) != 0)
-                continue;
-
-            /* Check if the keycodes or modifiers are different. If so, they
-             * can't be duplicate */
-            if (bind->keycode != current->keycode ||
-                bind->event_state_mask != current->event_state_mask ||
-                bind->release != current->release)
+            if (!binding_same_key(bind, current)) {
                 continue;
+            }
 
             context->has_errors = true;
             if (current->keycode != 0) {
diff --git a/src/click.c b/src/click.c
index 40edc1f58..62fb08ca2 100644
--- a/src/click.c
+++ b/src/click.c
@@ -218,8 +218,20 @@ static void route_click(Con *con, xcb_button_press_event_t *event, const bool mo
         goto done;
     }
 
-    /* 2: focus this con. */
-    con_activate(con);
+    /* 2: focus this con or one of its children. */
+    Con *con_to_focus = con;
+    if (in_stacked && dest == CLICK_DECORATION) {
+        /* If the container is a tab/stacked container and the click happened
+         * on a tab, switch to the tab. If the tab contents were already
+         * focused, focus the tab container itself. If the tab container was
+         * already focused, cycle back to focusing the tab contents. */
+        if (was_focused || !con_has_parent(focused, con)) {
+            while (!TAILQ_EMPTY(&(con_to_focus->focus_head))) {
+                con_to_focus = TAILQ_FIRST(&(con_to_focus->focus_head));
+            }
+        }
+    }
+    con_activate(con_to_focus);
 
     /* 3: For floating containers, we also want to raise them on click.
      * We will skip handling events on floating cons in fullscreen mode */
diff --git a/src/commands.c b/src/commands.c
index 7bbd6de77..51c9ce987 100644
--- a/src/commands.c
+++ b/src/commands.c
@@ -1024,23 +1024,113 @@ void cmd_mode(I3_CMD, const char *mode) {
 }
 
 /*
- * Implementation of 'move [window|container] [to] output <str>'.
+ * Implementation of 'move [window|container|workspace] [to] output <strings>'.
  *
  */
-void cmd_move_con_to_output(I3_CMD, const char *name) {
-    DLOG("Should move window to output \"%s\".\n", name);
+void cmd_move_con_to_output(I3_CMD, const char *name, bool move_workspace) {
+    /* Initialize a data structure that is used to save multiple user-specified
+     * output names since this function is called multiple types for each
+     * command call. */
+    typedef struct user_output_name {
+        char *name;
+        TAILQ_ENTRY(user_output_name) user_output_names;
+    } user_output_name;
+    static TAILQ_HEAD(user_output_names_head, user_output_name) user_output_names = TAILQ_HEAD_INITIALIZER(user_output_names);
+
+    if (name) {
+        if (strcmp(name, "next") == 0) {
+            /* "next" here works like a wildcard: It "expands" to all available
+             * outputs. */
+            Output *output;
+            TAILQ_FOREACH (output, &outputs, outputs) {
+                user_output_name *co = scalloc(sizeof(user_output_name), 1);
+                co->name = sstrdup(output_primary_name(output));
+                TAILQ_INSERT_TAIL(&user_output_names, co, user_output_names);
+            }
+            return;
+        }
+
+        user_output_name *co = scalloc(sizeof(user_output_name), 1);
+        co->name = sstrdup(name);
+        TAILQ_INSERT_TAIL(&user_output_names, co, user_output_names);
+        return;
+    }
+
     HANDLE_EMPTY_MATCH;
 
+    if (TAILQ_EMPTY(&user_output_names)) {
+        yerror("At least one output must be specified");
+        return;
+    }
+
+    bool success = false;
+    user_output_name *uo;
     owindow *current;
-    bool had_error = false;
     TAILQ_FOREACH (current, &owindows, owindows) {
-        DLOG("matching: %p / %s\n", current->con, current->con->name);
+        Con *ws = con_get_workspace(current->con);
+        if (con_is_internal(ws)) {
+            continue;
+        }
+
+        Output *current_output = get_output_for_con(ws);
+
+        Output *target_output = NULL;
+        TAILQ_FOREACH (uo, &user_output_names, user_output_names) {
+            if (strcasecmp(output_primary_name(current_output), uo->name) == 0) {
+                /* The current output is in the user list */
+                while (true) {
+                    /* This corrupts the outer loop but it is ok since we are
+                     * going to break anyway. */
+                    uo = TAILQ_NEXT(uo, user_output_names);
+                    if (!uo) {
+                        /* We reached the end of the list. We should use the
+                         * first available output that, if it exists, is
+                         * already saved in target_output. */
+                        break;
+                    }
+                    Output *out = get_output_from_string(current_output, uo->name);
+                    if (out) {
+                        DLOG("Found next target for workspace %s from user list: %s\n", ws->name, uo->name);
+                        target_output = out;
+                        break;
+                    }
+                }
+                break;
+            }
+            if (!target_output) {
+                /* The first available output from the list is used in 2 cases:
+                 * 1. When we must wrap around the user list. For example, if
+                 * user specifies outputs A B C and C is `current_output`.
+                 * 2. When the current output is not in the user list. For
+                 * example, user specifies A B C and D is `current_output`.
+                 */
+                DLOG("Found first target for workspace %s from user list: %s\n", ws->name, uo->name);
+                target_output = get_output_from_string(current_output, uo->name);
+            }
+        }
+        if (target_output) {
+            if (move_workspace) {
+                workspace_move_to_output(ws, target_output);
+            } else {
+                con_move_to_output(current->con, target_output, true);
+            }
+            success = true;
+        }
+    }
 
-        had_error |= !con_move_to_output_name(current->con, name, true);
+    while (!TAILQ_EMPTY(&user_output_names)) {
+        uo = TAILQ_FIRST(&user_output_names);
+        free(uo->name);
+        TAILQ_REMOVE(&user_output_names, uo, user_output_names);
+        free(uo);
     }
 
-    cmd_output->needs_tree_render = true;
-    ysuccess(!had_error);
+    cmd_output->needs_tree_render = success;
+    if (success) {
+        ysuccess(true);
+    } else {
+        yerror("No output matched");
+    }
 }
 
 /*
@@ -1094,36 +1184,6 @@ void cmd_floating(I3_CMD, const char *floating_mode) {
     ysuccess(true);
 }
 
-/*
- * Implementation of 'move workspace to [output] <str>'.
- *
- */
-void cmd_move_workspace_to_output(I3_CMD, const char *name) {
-    DLOG("should move workspace to output %s\n", name);
-
-    HANDLE_EMPTY_MATCH;
-
-    owindow *current;
-    TAILQ_FOREACH (current, &owindows, owindows) {
-        Con *ws = con_get_workspace(current->con);
-        if (con_is_internal(ws)) {
-            continue;
-        }
-
-        Output *current_output = get_output_for_con(ws);
-        Output *target_output = get_output_from_string(current_output, name);
-        if (!target_output) {
-            yerror("Could not get output from string \"%s\"", name);
-            return;
-        }
-
-        workspace_move_to_output(ws, target_output);
-    }
-
-    cmd_output->needs_tree_render = true;
-    ysuccess(true);
-}
-
 /*
  * Implementation of 'split v|h|t|vertical|horizontal|toggle'.
  *
@@ -1669,6 +1729,9 @@ void cmd_restart(I3_CMD) {
     }
     ipc_shutdown(SHUTDOWN_REASON_RESTART, exempt_fd);
     unlink(config.ipc_socket_path);
+    if (current_log_stream_socket_path != NULL) {
+        unlink(current_log_stream_socket_path);
+    }
     /* We need to call this manually since atexit handlers don’t get called
      * when exec()ing */
     purge_zerobyte_logfile();
@@ -1982,6 +2045,35 @@ void cmd_title_format(I3_CMD, const char *format) {
     ysuccess(true);
 }
 
+/*
+ * Implementation of 'title_window_icon <yes|no>' and 'title_window_icon padding <px>'
+ *
+ */
+void cmd_title_window_icon(I3_CMD, const char *enable, int padding) {
+    if (enable != NULL && !boolstr(enable)) {
+        padding = -1;
+    }
+    DLOG("setting window_icon=%d\n", padding);
+    HANDLE_EMPTY_MATCH;
+
+    owindow *current;
+    TAILQ_FOREACH (current, &owindows, owindows) {
+        DLOG("setting window_icon for %p / %s\n", current->con, current->con->name);
+        current->con->window_icon_padding = padding;
+
+        if (current->con->window != NULL) {
+            /* Make sure the window title is redrawn immediately. */
+            current->con->window->name_x_changed = true;
+        } else {
+            /* For windowless containers we also need to force the redrawing. */
+            FREE(current->con->deco_render_params);
+        }
+    }
+
+    cmd_output->needs_tree_render = true;
+    ysuccess(true);
+}
+
 /*
  * Implementation of 'rename workspace [<name>] to <name>'
  *
diff --git a/src/commands_parser.c b/src/commands_parser.c
index 6c7914151..fd02293dc 100644
--- a/src/commands_parser.c
+++ b/src/commands_parser.c
@@ -56,40 +56,19 @@ typedef struct tokenptr {
 
 #include "GENERATED_command_tokens.h"
 
-/*******************************************************************************
- * The (small) stack where identified literals are stored during the parsing
- * of a single command (like $workspace).
- ******************************************************************************/
-
-struct stack_entry {
-    /* Just a pointer, not dynamically allocated. */
-    const char *identifier;
-    enum {
-        STACK_STR = 0,
-        STACK_LONG = 1,
-    } type;
-    union {
-        char *str;
-        long num;
-    } val;
-};
-
-/* 10 entries should be enough for everybody. */
-static struct stack_entry stack[10];
-
 /*
  * Pushes a string (identified by 'identifier') on the stack. We simply use a
  * single array, since the number of entries we have to store is very small.
  *
  */
-static void push_string(const char *identifier, char *str) {
+static void push_string(struct stack *stack, const char *identifier, char *str) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier != NULL)
+        if (stack->stack[c].identifier != NULL)
             continue;
         /* Found a free slot, let’s store it here. */
-        stack[c].identifier = identifier;
-        stack[c].val.str = str;
-        stack[c].type = STACK_STR;
+        stack->stack[c].identifier = identifier;
+        stack->stack[c].val.str = str;
+        stack->stack[c].type = STACK_STR;
         return;
     }
 
@@ -103,15 +82,15 @@ static void push_string(const char *identifier, char *str) {
 }
 
 // TODO move to a common util
-static void push_long(const char *identifier, long num) {
+static void push_long(struct stack *stack, const char *identifier, long num) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier != NULL) {
+        if (stack->stack[c].identifier != NULL) {
             continue;
         }
 
-        stack[c].identifier = identifier;
-        stack[c].val.num = num;
-        stack[c].type = STACK_LONG;
+        stack->stack[c].identifier = identifier;
+        stack->stack[c].val.num = num;
+        stack->stack[c].type = STACK_LONG;
         return;
     }
 
@@ -125,36 +104,36 @@ static void push_long(const char *identifier, long num) {
 }
 
 // TODO move to a common util
-static const char *get_string(const char *identifier) {
+static const char *get_string(struct stack *stack, const char *identifier) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier == NULL)
+        if (stack->stack[c].identifier == NULL)
             break;
-        if (strcmp(identifier, stack[c].identifier) == 0)
-            return stack[c].val.str;
+        if (strcmp(identifier, stack->stack[c].identifier) == 0)
+            return stack->stack[c].val.str;
     }
     return NULL;
 }
 
 // TODO move to a common util
-static long get_long(const char *identifier) {
+static long get_long(struct stack *stack, const char *identifier) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier == NULL)
+        if (stack->stack[c].identifier == NULL)
             break;
-        if (strcmp(identifier, stack[c].identifier) == 0)
-            return stack[c].val.num;
+        if (strcmp(identifier, stack->stack[c].identifier) == 0)
+            return stack->stack[c].val.num;
     }
 
     return 0;
 }
 
 // TODO move to a common util
-static void clear_stack(void) {
+static void clear_stack(struct stack *stack) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].type == STACK_STR)
-            free(stack[c].val.str);
-        stack[c].identifier = NULL;
-        stack[c].val.str = NULL;
-        stack[c].val.num = 0;
+        if (stack->stack[c].type == STACK_STR)
+            free(stack->stack[c].val.str);
+        stack->stack[c].identifier = NULL;
+        stack->stack[c].val.str = NULL;
+        stack->stack[c].val.num = 0;
     }
 }
 
@@ -163,9 +142,12 @@ static void clear_stack(void) {
  ******************************************************************************/
 
 static cmdp_state state;
-#ifndef TEST_PARSER
 static Match current_match;
-#endif
+/*******************************************************************************
+ * The (small) stack where identified literals are stored during the parsing
+ * of a single command (like $workspace).
+ ******************************************************************************/
+static struct stack stack;
 static struct CommandResultIR subcommand_output;
 static struct CommandResultIR command_output;
 
@@ -176,19 +158,19 @@ static void next_state(const cmdp_token *token) {
         subcommand_output.json_gen = command_output.json_gen;
         subcommand_output.client = command_output.client;
         subcommand_output.needs_tree_render = false;
-        GENERATED_call(token->extra.call_identifier, &subcommand_output);
+        GENERATED_call(&current_match, &stack, token->extra.call_identifier, &subcommand_output);
         state = subcommand_output.next_state;
         /* If any subcommand requires a tree_render(), we need to make the
          * whole parser result request a tree_render(). */
         if (subcommand_output.needs_tree_render)
             command_output.needs_tree_render = true;
-        clear_stack();
+        clear_stack(&stack);
         return;
     }
 
     state = token->next_state;
     if (state == INITIAL) {
-        clear_stack();
+        clear_stack(&stack);
     }
 }
 
@@ -296,8 +278,9 @@ CommandResult *parse_command(const char *input, yajl_gen gen, ipc_client *client
             /* A literal. */
             if (token->name[0] == '\'') {
                 if (strncasecmp(walk, token->name + 1, strlen(token->name) - 1) == 0) {
-                    if (token->identifier != NULL)
-                        push_string(token->identifier, sstrdup(token->name + 1));
+                    if (token->identifier != NULL) {
+                        push_string(&stack, token->identifier, sstrdup(token->name + 1));
+                    }
                     walk += strlen(token->name) - 1;
                     next_state(token);
                     token_handled = true;
@@ -319,8 +302,9 @@ CommandResult *parse_command(const char *input, yajl_gen gen, ipc_client *client
                 if (end == walk)
                     continue;
 
-                if (token->identifier != NULL)
-                    push_long(token->identifier, num);
+                if (token->identifier != NULL) {
+                    push_long(&stack, token->identifier, num);
+                }
 
                 /* Set walk to the first non-number character */
                 walk = end;
@@ -333,8 +317,9 @@ CommandResult *parse_command(const char *input, yajl_gen gen, ipc_client *client
                 strcmp(token->name, "word") == 0) {
                 char *str = parse_string(&walk, (token->name[0] != 's'));
                 if (str != NULL) {
-                    if (token->identifier)
-                        push_string(token->identifier, str);
+                    if (token->identifier) {
+                        push_string(&stack, token->identifier, str);
+                    }
                     /* If we are at the end of a quoted string, skip the ending
                      * double quote. */
                     if (*walk == '"')
@@ -436,7 +421,7 @@ CommandResult *parse_command(const char *input, yajl_gen gen, ipc_client *client
             y(map_close);
 
             free(position);
-            clear_stack();
+            clear_stack(&stack);
             break;
         }
     }
diff --git a/src/con.c b/src/con.c
index 445d29001..d8c0e908d 100644
--- a/src/con.c
+++ b/src/con.c
@@ -43,6 +43,7 @@ Con *con_new_skeleton(Con *parent, i3Window *window) {
     new->window = window;
     new->border_style = config.default_border;
     new->current_border_width = -1;
+    new->window_icon_padding = -1;
     if (window) {
         new->depth = window->depth;
     } else {
@@ -1873,9 +1874,9 @@ void con_set_layout(Con *con, layout_t layout) {
             con_attach(new, con, false);
 
             tree_flatten(croot);
+            con_force_split_parents_redraw(con);
+            return;
         }
-        con_force_split_parents_redraw(con);
-        return;
     }
 
     if (layout == L_DEFAULT) {
@@ -2361,20 +2362,25 @@ i3String *con_parse_title_format(Con *con) {
     char *title;
     char *class;
     char *instance;
+    char *machine;
     if (win == NULL) {
         title = pango_escape_markup(con_get_tree_representation(con));
         class = sstrdup("i3-frame");
         instance = sstrdup("i3-frame");
+        machine = sstrdup("");
     } else {
         title = pango_escape_markup(sstrdup((win->name == NULL) ? "" : i3string_as_utf8(win->name)));
         class = pango_escape_markup(sstrdup((win->class_class == NULL) ? "" : win->class_class));
         instance = pango_escape_markup(sstrdup((win->class_instance == NULL) ? "" : win->class_instance));
+        machine = pango_escape_markup(sstrdup((win->machine == NULL) ? "" : win->machine));
     }
 
     placeholder_t placeholders[] = {
         {.name = "%title", .value = title},
         {.name = "%class", .value = class},
-        {.name = "%instance", .value = instance}};
+        {.name = "%instance", .value = instance},
+        {.name = "%machine", .value = machine},
+    };
     const size_t num = sizeof(placeholders) / sizeof(placeholder_t);
 
     char *formatted_str = format_placeholders(con->title_format, &placeholders[0], num);
diff --git a/src/config.c b/src/config.c
index 77ba38cbd..003b3dbd4 100644
--- a/src/config.c
+++ b/src/config.c
@@ -10,13 +10,16 @@
  */
 #include "all.h"
 
+#include <libgen.h>
+#include <unistd.h>
+
 #include <xkbcommon/xkbcommon.h>
 
 char *current_configpath = NULL;
-char *current_config = NULL;
 Config config;
 struct modes_head modes;
 struct barconfig_head barconfigs = TAILQ_HEAD_INITIALIZER(barconfigs);
+struct includedfiles_head included_files = TAILQ_HEAD_INITIALIZER(included_files);
 
 /*
  * Ungrabs all keys, to be called before re-grabbing the keys because of a
@@ -231,8 +234,43 @@ bool load_configuration(const char *override_configpath, config_load_t load_type
             "$XDG_CONFIG_HOME/i3/config, ~/.i3/config, $XDG_CONFIG_DIRS/i3/config "
             "and " SYSCONFDIR "/i3/config)");
     }
-    LOG("Parsing configfile %s\n", current_configpath);
-    const bool result = parse_file(current_configpath, load_type != C_VALIDATE);
+
+    IncludedFile *file;
+    while (!TAILQ_EMPTY(&included_files)) {
+        file = TAILQ_FIRST(&included_files);
+        FREE(file->path);
+        FREE(file->raw_contents);
+        FREE(file->variable_replaced_contents);
+        TAILQ_REMOVE(&included_files, file, files);
+        FREE(file);
+    }
+
+    char resolved_path[PATH_MAX] = {'\0'};
+    if (realpath(current_configpath, resolved_path) == NULL) {
+        die("realpath(%s): %s", current_configpath, strerror(errno));
+    }
+
+    file = scalloc(1, sizeof(IncludedFile));
+    file->path = sstrdup(resolved_path);
+    TAILQ_INSERT_TAIL(&included_files, file, files);
+
+    LOG("Parsing configfile %s\n", resolved_path);
+    struct stack stack;
+    memset(&stack, '\0', sizeof(struct stack));
+    struct parser_ctx ctx = {
+        .use_nagbar = (load_type != C_VALIDATE),
+        .assume_v4 = false,
+        .stack = &stack,
+    };
+    SLIST_INIT(&(ctx.variables));
+    const int result = parse_file(&ctx, resolved_path, file);
+    free_variables(&ctx);
+    if (result == -1) {
+        die("Could not open configuration file: %s\n", strerror(errno));
+    }
+
+    extract_workspace_names_from_bindings();
+    reorder_bindings();
 
     if (config.font.type == FONT_TYPE_NONE && load_type != C_VALIDATE) {
         ELOG("You did not specify required configuration option \"font\"\n");
@@ -251,5 +289,5 @@ bool load_configuration(const char *override_configpath, config_load_t load_type
         xcb_flush(conn);
     }
 
-    return result;
+    return result == 0;
 }
diff --git a/src/config_directives.c b/src/config_directives.c
index 52362547a..6d461c340 100644
--- a/src/config_directives.c
+++ b/src/config_directives.c
@@ -9,6 +9,86 @@
  */
 #include "all.h"
 
+#include <wordexp.h>
+
+/*******************************************************************************
+ * Include functions.
+ ******************************************************************************/
+
+CFGFUN(include, const char *pattern) {
+    DLOG("include %s\n", pattern);
+
+    wordexp_t p;
+    const int ret = wordexp(pattern, &p, 0);
+    if (ret != 0) {
+        ELOG("wordexp(%s): error %d\n", pattern, ret);
+        result->has_errors = true;
+        return;
+    }
+    char **w = p.we_wordv;
+    for (size_t i = 0; i < p.we_wordc; i++) {
+        char resolved_path[PATH_MAX] = {'\0'};
+        if (realpath(w[i], resolved_path) == NULL) {
+            LOG("Skipping %s: %s\n", w[i], strerror(errno));
+            continue;
+        }
+
+        bool skip = false;
+        IncludedFile *file;
+        TAILQ_FOREACH (file, &included_files, files) {
+            if (strcmp(file->path, resolved_path) == 0) {
+                skip = true;
+                break;
+            }
+        }
+        if (skip) {
+            LOG("Skipping file %s (already included)\n", resolved_path);
+            continue;
+        }
+
+        LOG("Including config file %s\n", resolved_path);
+
+        file = scalloc(1, sizeof(IncludedFile));
+        file->path = sstrdup(resolved_path);
+        TAILQ_INSERT_TAIL(&included_files, file, files);
+
+        struct stack stack;
+        memset(&stack, '\0', sizeof(struct stack));
+        struct parser_ctx ctx = {
+            .use_nagbar = result->ctx->use_nagbar,
+            /* The include mechanism was added in v4, so we can skip the
+             * auto-detection and get rid of the risk of detecting the wrong
+             * version in potentially very short include fragments: */
+            .assume_v4 = true,
+            .stack = &stack,
+            .variables = result->ctx->variables,
+        };
+        switch (parse_file(&ctx, resolved_path, file)) {
+            case PARSE_FILE_SUCCESS:
+                break;
+
+            case PARSE_FILE_FAILED:
+                ELOG("including config file %s: %s\n", resolved_path, strerror(errno));
+                /* fallthrough */
+
+            case PARSE_FILE_CONFIG_ERRORS:
+                result->has_errors = true;
+                TAILQ_REMOVE(&included_files, file, files);
+                FREE(file->path);
+                FREE(file->raw_contents);
+                FREE(file->variable_replaced_contents);
+                FREE(file);
+                break;
+
+            default:
+                /* missing case statement */
+                assert(false);
+                break;
+        }
+    }
+    wordfree(&p);
+}
+
 /*******************************************************************************
  * Criteria functions.
  ******************************************************************************/
@@ -45,15 +125,6 @@ CFGFUN(criteria_add, const char *ctype, const char *cvalue) {
  * Utility functions
  ******************************************************************************/
 
-static bool eval_boolstr(const char *str) {
-    return (strcasecmp(str, "1") == 0 ||
-            strcasecmp(str, "yes") == 0 ||
-            strcasecmp(str, "true") == 0 ||
-            strcasecmp(str, "on") == 0 ||
-            strcasecmp(str, "enable") == 0 ||
-            strcasecmp(str, "active") == 0);
-}
-
 /*
  * A utility function to convert a string containing the group and modifiers to
  * the corresponding bit mask.
@@ -305,14 +376,14 @@ CFGFUN(smart_borders, const char *enable) {
     if (!strcmp(enable, "no_gaps"))
         config.smart_borders = SMART_BORDERS_NO_GAPS;
     else
-        config.smart_borders = eval_boolstr(enable) ? SMART_BORDERS_ON : SMART_BORDERS_OFF;
+        config.smart_borders = boolstr(enable) ? SMART_BORDERS_ON : SMART_BORDERS_OFF;
 }
 
 CFGFUN(smart_gaps, const char *enable) {
     if (!strcmp(enable, "inverse_outer"))
         config.smart_gaps = SMART_GAPS_INVERSE_OUTER;
     else
-        config.smart_gaps = eval_boolstr(enable) ? SMART_GAPS_ON : SMART_GAPS_OFF;
+        config.smart_gaps = boolstr(enable) ? SMART_GAPS_ON : SMART_GAPS_OFF;
 }
 
 CFGFUN(floating_minimum_size, const long width, const long height) {
@@ -393,14 +464,14 @@ CFGFUN(hide_edge_borders, const char *borders) {
         config.hide_edge_borders = HEBM_BOTH;
     else if (strcmp(borders, "none") == 0)
         config.hide_edge_borders = HEBM_NONE;
-    else if (eval_boolstr(borders))
+    else if (boolstr(borders))
         config.hide_edge_borders = HEBM_VERTICAL;
     else
         config.hide_edge_borders = HEBM_NONE;
 }
 
 CFGFUN(focus_follows_mouse, const char *value) {
-    config.disable_focus_follows_mouse = !eval_boolstr(value);
+    config.disable_focus_follows_mouse = !boolstr(value);
 }
 
 CFGFUN(mouse_warping, const char *value) {
@@ -411,11 +482,11 @@ CFGFUN(mouse_warping, const char *value) {
 }
 
 CFGFUN(force_xinerama, const char *value) {
-    config.force_xinerama = eval_boolstr(value);
+    config.force_xinerama = boolstr(value);
 }
 
 CFGFUN(disable_randr15, const char *value) {
-    config.disable_randr15 = eval_boolstr(value);
+    config.disable_randr15 = boolstr(value);
 }
 
 CFGFUN(focus_wrapping, const char *value) {
@@ -423,7 +494,7 @@ CFGFUN(focus_wrapping, const char *value) {
         config.focus_wrapping = FOCUS_WRAPPING_FORCE;
     } else if (strcmp(value, "workspace") == 0) {
         config.focus_wrapping = FOCUS_WRAPPING_WORKSPACE;
-    } else if (eval_boolstr(value)) {
+    } else if (boolstr(value)) {
         config.focus_wrapping = FOCUS_WRAPPING_ON;
     } else {
         config.focus_wrapping = FOCUS_WRAPPING_OFF;
@@ -432,7 +503,7 @@ CFGFUN(focus_wrapping, const char *value) {
 
 CFGFUN(force_focus_wrapping, const char *value) {
     /* Legacy syntax. */
-    if (eval_boolstr(value)) {
+    if (boolstr(value)) {
         config.focus_wrapping = FOCUS_WRAPPING_FORCE;
     } else {
         /* For "force_focus_wrapping off", don't enable or disable
@@ -444,7 +515,7 @@ CFGFUN(force_focus_wrapping, const char *value) {
 }
 
 CFGFUN(workspace_back_and_forth, const char *value) {
-    config.workspace_auto_back_and_forth = eval_boolstr(value);
+    config.workspace_auto_back_and_forth = boolstr(value);
 }
 
 CFGFUN(fake_outputs, const char *outputs) {
@@ -486,7 +557,7 @@ CFGFUN(title_align, const char *alignment) {
 }
 
 CFGFUN(show_marks, const char *value) {
-    config.show_marks = eval_boolstr(value);
+    config.show_marks = boolstr(value);
 }
 
 static char *current_workspace = NULL;
@@ -676,7 +747,7 @@ CFGFUN(bar_output, const char *output) {
 }
 
 CFGFUN(bar_verbose, const char *verbose) {
-    current_bar->verbose = eval_boolstr(verbose);
+    current_bar->verbose = boolstr(verbose);
 }
 
 CFGFUN(bar_height, const long height) {
@@ -800,11 +871,11 @@ CFGFUN(bar_status_command, const char *command) {
 }
 
 CFGFUN(bar_binding_mode_indicator, const char *value) {
-    current_bar->hide_binding_mode_indicator = !eval_boolstr(value);
+    current_bar->hide_binding_mode_indicator = !boolstr(value);
 }
 
 CFGFUN(bar_workspace_buttons, const char *value) {
-    current_bar->hide_workspace_buttons = !eval_boolstr(value);
+    current_bar->hide_workspace_buttons = !boolstr(value);
 }
 
 CFGFUN(bar_workspace_min_width, const long width) {
@@ -812,11 +883,11 @@ CFGFUN(bar_workspace_min_width, const long width) {
 }
 
 CFGFUN(bar_strip_workspace_numbers, const char *value) {
-    current_bar->strip_workspace_numbers = eval_boolstr(value);
+    current_bar->strip_workspace_numbers = boolstr(value);
 }
 
 CFGFUN(bar_strip_workspace_name, const char *value) {
-    current_bar->strip_workspace_name = eval_boolstr(value);
+    current_bar->strip_workspace_name = boolstr(value);
 }
 
 CFGFUN(bar_start) {
diff --git a/src/config_parser.c b/src/config_parser.c
index f78e75f83..860ea86f9 100644
--- a/src/config_parser.c
+++ b/src/config_parser.c
@@ -35,18 +35,14 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
+#include <libgen.h>
 
 #include <xcb/xcb_xrm.h>
 
-// Macros to make the YAJL API a bit easier to use.
-#define y(x, ...) yajl_gen_##x(command_output.json_gen, ##__VA_ARGS__)
-#define ystr(str) yajl_gen_string(command_output.json_gen, (unsigned char *)str, strlen(str))
-
 xcb_xrm_database_t *database = NULL;
 
 #ifndef TEST_PARSER
 pid_t config_error_nagbar_pid = -1;
-static struct context *context;
 #endif
 
 /*******************************************************************************
@@ -76,46 +72,25 @@ typedef struct tokenptr {
 
 #include "GENERATED_config_tokens.h"
 
-/*******************************************************************************
- * The (small) stack where identified literals are stored during the parsing
- * of a single command (like $workspace).
- ******************************************************************************/
-
-struct stack_entry {
-    /* Just a pointer, not dynamically allocated. */
-    const char *identifier;
-    enum {
-        STACK_STR = 0,
-        STACK_LONG = 1,
-    } type;
-    union {
-        char *str;
-        long num;
-    } val;
-};
-
-/* 10 entries should be enough for everybody. */
-static struct stack_entry stack[10];
-
 /*
  * Pushes a string (identified by 'identifier') on the stack. We simply use a
  * single array, since the number of entries we have to store is very small.
  *
  */
-static void push_string(const char *identifier, const char *str) {
+static void push_string(struct stack *ctx, const char *identifier, const char *str) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier != NULL &&
-            strcmp(stack[c].identifier, identifier) != 0)
+        if (ctx->stack[c].identifier != NULL &&
+            strcmp(ctx->stack[c].identifier, identifier) != 0)
             continue;
-        if (stack[c].identifier == NULL) {
+        if (ctx->stack[c].identifier == NULL) {
             /* Found a free slot, let’s store it here. */
-            stack[c].identifier = identifier;
-            stack[c].val.str = sstrdup(str);
-            stack[c].type = STACK_STR;
+            ctx->stack[c].identifier = identifier;
+            ctx->stack[c].val.str = sstrdup(str);
+            ctx->stack[c].type = STACK_STR;
         } else {
             /* Append the value. */
-            char *prev = stack[c].val.str;
-            sasprintf(&(stack[c].val.str), "%s,%s", prev, str);
+            char *prev = ctx->stack[c].val.str;
+            sasprintf(&(ctx->stack[c].val.str), "%s,%s", prev, str);
             free(prev);
         }
         return;
@@ -130,14 +105,15 @@ static void push_string(const char *identifier, const char *str) {
     exit(EXIT_FAILURE);
 }
 
-static void push_long(const char *identifier, long num) {
+static void push_long(struct stack *ctx, const char *identifier, long num) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier != NULL)
+        if (ctx->stack[c].identifier != NULL) {
             continue;
+        }
         /* Found a free slot, let’s store it here. */
-        stack[c].identifier = identifier;
-        stack[c].val.num = num;
-        stack[c].type = STACK_LONG;
+        ctx->stack[c].identifier = identifier;
+        ctx->stack[c].val.num = num;
+        ctx->stack[c].type = STACK_LONG;
         return;
     }
 
@@ -150,33 +126,33 @@ static void push_long(const char *identifier, long num) {
     exit(EXIT_FAILURE);
 }
 
-static const char *get_string(const char *identifier) {
+static const char *get_string(struct stack *ctx, const char *identifier) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier == NULL)
+        if (ctx->stack[c].identifier == NULL)
             break;
-        if (strcmp(identifier, stack[c].identifier) == 0)
-            return stack[c].val.str;
+        if (strcmp(identifier, ctx->stack[c].identifier) == 0)
+            return ctx->stack[c].val.str;
     }
     return NULL;
 }
 
-static long get_long(const char *identifier) {
+static long get_long(struct stack *ctx, const char *identifier) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].identifier == NULL)
+        if (ctx->stack[c].identifier == NULL)
             break;
-        if (strcmp(identifier, stack[c].identifier) == 0)
-            return stack[c].val.num;
+        if (strcmp(identifier, ctx->stack[c].identifier) == 0)
+            return ctx->stack[c].val.num;
     }
     return 0;
 }
 
-static void clear_stack(void) {
+static void clear_stack(struct stack *ctx) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].type == STACK_STR)
-            free(stack[c].val.str);
-        stack[c].identifier = NULL;
-        stack[c].val.str = NULL;
-        stack[c].val.num = 0;
+        if (ctx->stack[c].type == STACK_STR)
+            free(ctx->stack[c].val.str);
+        ctx->stack[c].identifier = NULL;
+        ctx->stack[c].val.str = NULL;
+        ctx->stack[c].val.num = 0;
     }
 }
 
@@ -184,50 +160,42 @@ static void clear_stack(void) {
  * The parser itself.
  ******************************************************************************/
 
-static cmdp_state state;
-static Match current_match;
-static struct ConfigResultIR subcommand_output;
-static struct ConfigResultIR command_output;
-
-/* A list which contains the states that lead to the current state, e.g.
- * INITIAL, WORKSPACE_LAYOUT.
- * When jumping back to INITIAL, statelist_idx will simply be set to 1
- * (likewise for other states, e.g. MODE or BAR).
- * This list is used to process the nearest error token. */
-static cmdp_state statelist[10] = {INITIAL};
-/* NB: statelist_idx points to where the next entry will be inserted */
-static int statelist_idx = 1;
-
 #include "GENERATED_config_call.h"
 
-static void next_state(const cmdp_token *token) {
+static void next_state(const cmdp_token *token, struct parser_ctx *ctx) {
     cmdp_state _next_state = token->next_state;
 
     //printf("token = name %s identifier %s\n", token->name, token->identifier);
     //printf("next_state = %d\n", token->next_state);
     if (token->next_state == __CALL) {
-        subcommand_output.json_gen = command_output.json_gen;
-        GENERATED_call(token->extra.call_identifier, &subcommand_output);
+        struct ConfigResultIR subcommand_output = {
+            .ctx = ctx,
+        };
+        GENERATED_call(&(ctx->current_match), ctx->stack, token->extra.call_identifier, &subcommand_output);
+        if (subcommand_output.has_errors) {
+            ctx->has_errors = true;
+        }
         _next_state = subcommand_output.next_state;
-        clear_stack();
+        clear_stack(ctx->stack);
     }
 
-    state = _next_state;
-    if (state == INITIAL) {
-        clear_stack();
+    ctx->state = _next_state;
+    if (ctx->state == INITIAL) {
+        clear_stack(ctx->stack);
     }
 
     /* See if we are jumping back to a state in which we were in previously
      * (statelist contains INITIAL) and just move statelist_idx accordingly. */
-    for (int i = 0; i < statelist_idx; i++) {
-        if (statelist[i] != _next_state)
+    for (int i = 0; i < ctx->statelist_idx; i++) {
+        if ((cmdp_state)(ctx->statelist[i]) != _next_state) {
             continue;
-        statelist_idx = i + 1;
+        }
+        ctx->statelist_idx = i + 1;
         return;
     }
 
     /* Otherwise, the state is new and we add it to the list */
-    statelist[statelist_idx++] = _next_state;
+    ctx->statelist[ctx->statelist_idx++] = _next_state;
 }
 
 /*
@@ -257,7 +225,7 @@ static char *single_line(const char *start) {
     return result;
 }
 
-struct ConfigResultIR *parse_config(const char *input, struct context *context) {
+static void parse_config(struct parser_ctx *ctx, const char *input, struct context *context) {
     /* Dump the entire config file into the debug log. We cannot just use
      * DLOG("%s", input); because one log message must not exceed 4 KiB. */
     const char *dumpwalk = input;
@@ -273,13 +241,11 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
         }
         linecnt++;
     }
-    state = INITIAL;
-    statelist_idx = 1;
-
-    /* A YAJL JSON generator used for formatting replies. */
-    command_output.json_gen = yajl_gen_alloc(NULL);
-
-    y(array_open);
+    ctx->state = INITIAL;
+    for (int i = 0; i < 10; i++) {
+        ctx->statelist[i] = INITIAL;
+    }
+    ctx->statelist_idx = 1;
 
     const char *walk = input;
     const size_t len = strlen(input);
@@ -290,7 +256,10 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
 
 // TODO: make this testable
 #ifndef TEST_PARSER
-    cfg_criteria_init(&current_match, &subcommand_output, INITIAL);
+    struct ConfigResultIR subcommand_output = {
+        .ctx = ctx,
+    };
+    cfg_criteria_init(&(ctx->current_match), &subcommand_output, INITIAL);
 #endif
 
     /* The "<=" operator is intentional: We also handle the terminating 0-byte
@@ -303,7 +272,7 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
 
         //printf("remaining input: %s\n", walk);
 
-        cmdp_token_ptr *ptr = &(tokens[state]);
+        cmdp_token_ptr *ptr = &(tokens[ctx->state]);
         token_handled = false;
         for (c = 0; c < ptr->n; c++) {
             token = &(ptr->array[c]);
@@ -311,10 +280,11 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
             /* A literal. */
             if (token->name[0] == '\'') {
                 if (strncasecmp(walk, token->name + 1, strlen(token->name) - 1) == 0) {
-                    if (token->identifier != NULL)
-                        push_string(token->identifier, token->name + 1);
+                    if (token->identifier != NULL) {
+                        push_string(ctx->stack, token->identifier, token->name + 1);
+                    }
                     walk += strlen(token->name) - 1;
-                    next_state(token);
+                    next_state(token, ctx);
                     token_handled = true;
                     break;
                 }
@@ -334,12 +304,13 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
                 if (end == walk)
                     continue;
 
-                if (token->identifier != NULL)
-                    push_long(token->identifier, num);
+                if (token->identifier != NULL) {
+                    push_long(ctx->stack, token->identifier, num);
+                }
 
                 /* Set walk to the first non-number character */
                 walk = end;
-                next_state(token);
+                next_state(token, ctx);
                 token_handled = true;
                 break;
             }
@@ -382,14 +353,15 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
                             inpos++;
                         str[outpos] = beginning[inpos];
                     }
-                    if (token->identifier)
-                        push_string(token->identifier, str);
+                    if (token->identifier) {
+                        push_string(ctx->stack, token->identifier, str);
+                    }
                     free(str);
                     /* If we are at the end of a quoted string, skip the ending
                      * double quote. */
                     if (*walk == '"')
                         walk++;
-                    next_state(token);
+                    next_state(token, ctx);
                     token_handled = true;
                     break;
                 }
@@ -398,7 +370,7 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
             if (strcmp(token->name, "line") == 0) {
                 while (*walk != '\0' && *walk != '\n' && *walk != '\r')
                     walk++;
-                next_state(token);
+                next_state(token, ctx);
                 token_handled = true;
                 linecnt++;
                 walk++;
@@ -408,7 +380,7 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
             if (strcmp(token->name, "end") == 0) {
                 //printf("checking for end: *%s*\n", walk);
                 if (*walk == '\0' || *walk == '\n' || *walk == '\r') {
-                    next_state(token);
+                    next_state(token, ctx);
                     token_handled = true;
                     /* To make sure we start with an appropriate matching
                      * datastructure for commands which do *not* specify any
@@ -416,7 +388,7 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
                      * every command. */
 // TODO: make this testable
 #ifndef TEST_PARSER
-                    cfg_criteria_init(&current_match, &subcommand_output, INITIAL);
+                    cfg_criteria_init(&(ctx->current_match), &subcommand_output, INITIAL);
 #endif
                     linecnt++;
                     walk++;
@@ -515,41 +487,24 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
 
             context->has_errors = true;
 
-            /* Format this error message as a JSON reply. */
-            y(map_open);
-            ystr("success");
-            y(bool, false);
-            /* We set parse_error to true to distinguish this from other
-             * errors. i3-nagbar is spawned upon keypresses only for parser
-             * errors. */
-            ystr("parse_error");
-            y(bool, true);
-            ystr("error");
-            ystr(errormessage);
-            ystr("input");
-            ystr(input);
-            ystr("errorposition");
-            ystr(position);
-            y(map_close);
-
             /* Skip the rest of this line, but continue parsing. */
             while ((size_t)(walk - input) <= len && *walk != '\n')
                 walk++;
 
             free(position);
             free(errormessage);
-            clear_stack();
+            clear_stack(ctx->stack);
 
             /* To figure out in which state to go (e.g. MODE or INITIAL),
              * we find the nearest state which contains an <error> token
              * and follow that one. */
             bool error_token_found = false;
-            for (int i = statelist_idx - 1; (i >= 0) && !error_token_found; i--) {
-                cmdp_token_ptr *errptr = &(tokens[statelist[i]]);
+            for (int i = ctx->statelist_idx - 1; (i >= 0) && !error_token_found; i--) {
+                cmdp_token_ptr *errptr = &(tokens[ctx->statelist[i]]);
                 for (int j = 0; j < errptr->n; j++) {
                     if (strcmp(errptr->array[j].name, "error") != 0)
                         continue;
-                    next_state(&(errptr->array[j]));
+                    next_state(&(errptr->array[j]), ctx);
                     error_token_found = true;
                     break;
                 }
@@ -558,10 +513,6 @@ struct ConfigResultIR *parse_config(const char *input, struct context *context)
             assert(error_token_found);
         }
     }
-
-    y(array_close);
-
-    return &command_output;
 }
 
 /*******************************************************************************
@@ -612,9 +563,17 @@ int main(int argc, char *argv[]) {
         fprintf(stderr, "Syntax: %s <command>\n", argv[0]);
         return 1;
     }
+    struct stack stack;
+    memset(&stack, '\0', sizeof(struct stack));
+    struct parser_ctx ctx = {
+        .use_nagbar = false,
+        .assume_v4 = false,
+        .stack = &stack,
+    };
+    SLIST_INIT(&(ctx.variables));
     struct context context;
     context.filename = "<stdin>";
-    parse_config(argv[1], &context);
+    parse_config(&ctx, argv[1], &context);
 }
 
 #else
@@ -636,6 +595,7 @@ static int detect_version(char *buf) {
 
         /* check for some v4-only statements */
         if (strncasecmp(line, "bindcode", strlen("bindcode")) == 0 ||
+            strncasecmp(line, "include", strlen("include")) == 0 ||
             strncasecmp(line, "force_focus_wrapping", strlen("force_focus_wrapping")) == 0 ||
             strncasecmp(line, "# i3 config file (v4)", strlen("# i3 config file (v4)")) == 0 ||
             strncasecmp(line, "workspace_layout", strlen("workspace_layout")) == 0) {
@@ -877,34 +837,63 @@ static char *get_resource(char *name) {
     return resource;
 }
 
+/*
+ * Releases the memory of all variables in ctx.
+ *
+ */
+void free_variables(struct parser_ctx *ctx) {
+    struct Variable *current;
+    while (!SLIST_EMPTY(&(ctx->variables))) {
+        current = SLIST_FIRST(&(ctx->variables));
+        FREE(current->key);
+        FREE(current->value);
+        SLIST_REMOVE_HEAD(&(ctx->variables), variables);
+        FREE(current);
+    }
+}
+
 /*
  * Parses the given file by first replacing the variables, then calling
  * parse_config and possibly launching i3-nagbar.
  *
  */
-bool parse_file(const char *f, bool use_nagbar) {
-    struct variables_head variables = SLIST_HEAD_INITIALIZER(&variables);
+parse_file_result_t parse_file(struct parser_ctx *ctx, const char *f, IncludedFile *included_file) {
     int fd;
     struct stat stbuf;
     char *buf;
     FILE *fstr;
     char buffer[4096], key[512], value[4096], *continuation = NULL;
 
-    if ((fd = open(f, O_RDONLY)) == -1)
-        die("Could not open configuration file: %s\n", strerror(errno));
+    char *old_dir = get_current_dir_name();
+    char *dir = NULL;
+    /* dirname(3) might modify the buffer, so make a copy: */
+    char *dirbuf = sstrdup(f);
+    if ((dir = dirname(dirbuf)) != NULL) {
+        LOG("Changing working directory to config file directory %s\n", dir);
+        if (chdir(dir) == -1) {
+            ELOG("chdir(%s) failed: %s\n", dir, strerror(errno));
+            return PARSE_FILE_FAILED;
+        }
+    }
+    free(dirbuf);
 
-    if (fstat(fd, &stbuf) == -1)
-        die("Could not fstat file: %s\n", strerror(errno));
+    if ((fd = open(f, O_RDONLY)) == -1) {
+        return PARSE_FILE_FAILED;
+    }
+
+    if (fstat(fd, &stbuf) == -1) {
+        return PARSE_FILE_FAILED;
+    }
 
     buf = scalloc(stbuf.st_size + 1, 1);
 
-    if ((fstr = fdopen(fd, "r")) == NULL)
-        die("Could not fdopen: %s\n", strerror(errno));
+    if ((fstr = fdopen(fd, "r")) == NULL) {
+        return PARSE_FILE_FAILED;
+    }
 
-    FREE(current_config);
-    current_config = scalloc(stbuf.st_size + 1, 1);
-    if ((ssize_t)fread(current_config, 1, stbuf.st_size, fstr) != stbuf.st_size) {
-        die("Could not fread: %s\n", strerror(errno));
+    included_file->raw_contents = scalloc(stbuf.st_size + 1, 1);
+    if ((ssize_t)fread(included_file->raw_contents, 1, stbuf.st_size, fstr) != stbuf.st_size) {
+        return PARSE_FILE_FAILED;
     }
     rewind(fstr);
 
@@ -916,7 +905,7 @@ bool parse_file(const char *f, bool use_nagbar) {
         if (fgets(continuation, sizeof(buffer) - (continuation - buffer), fstr) == NULL) {
             if (feof(fstr))
                 break;
-            die("Could not read configuration file\n");
+            return PARSE_FILE_FAILED;
         }
         if (buffer[strlen(buffer) - 1] != '\n' && !feof(fstr)) {
             ELOG("Your line continuation is too long, it exceeds %zd bytes\n", sizeof(buffer));
@@ -960,7 +949,7 @@ bool parse_file(const char *f, bool use_nagbar) {
                 continue;
             }
 
-            upsert_variable(&variables, v_key, v_value);
+            upsert_variable(&(ctx->variables), v_key, v_value);
             continue;
         } else if (strcasecmp(key, "set_from_resource") == 0) {
             char res_name[512] = {'\0'};
@@ -993,7 +982,7 @@ bool parse_file(const char *f, bool use_nagbar) {
                 res_value = sstrdup(fallback);
             }
 
-            upsert_variable(&variables, v_key, res_value);
+            upsert_variable(&(ctx->variables), v_key, res_value);
             FREE(res_value);
             continue;
         }
@@ -1014,7 +1003,7 @@ bool parse_file(const char *f, bool use_nagbar) {
      * variables (otherwise we will count them twice, which is bad when
      * 'extra' is negative) */
     char *bufcopy = sstrdup(buf);
-    SLIST_FOREACH (current, &variables, variables) {
+    SLIST_FOREACH (current, &(ctx->variables), variables) {
         int extra = (strlen(current->value) - strlen(current->key));
         char *next;
         for (next = bufcopy;
@@ -1034,12 +1023,12 @@ bool parse_file(const char *f, bool use_nagbar) {
     destwalk = new;
     while (walk < (buf + stbuf.st_size)) {
         /* Find the next variable */
-        SLIST_FOREACH (current, &variables, variables) {
+        SLIST_FOREACH (current, &(ctx->variables), variables) {
             current->next_match = strcasestr(walk, current->key);
         }
         nearest = NULL;
         int distance = stbuf.st_size;
-        SLIST_FOREACH (current, &variables, variables) {
+        SLIST_FOREACH (current, &(ctx->variables), variables) {
             if (current->next_match == NULL)
                 continue;
             if ((current->next_match - walk) < distance) {
@@ -1064,7 +1053,10 @@ bool parse_file(const char *f, bool use_nagbar) {
 
     /* analyze the string to find out whether this is an old config file (3.x)
      * or a new config file (4.x). If it’s old, we run the converter script. */
-    int version = detect_version(buf);
+    int version = 4;
+    if (!ctx->assume_v4) {
+        version = detect_version(buf);
+    }
     if (version == 3) {
         /* We need to convert this v3 configuration */
         char *converted = migrate_config(new, strlen(new));
@@ -1090,17 +1082,18 @@ bool parse_file(const char *f, bool use_nagbar) {
         }
     }
 
-    context = scalloc(1, sizeof(struct context));
-    context->filename = f;
+    included_file->variable_replaced_contents = sstrdup(new);
 
-    struct ConfigResultIR *config_output = parse_config(new, context);
-    yajl_gen_free(config_output->json_gen);
+    struct context *context = scalloc(1, sizeof(struct context));
+    context->filename = f;
+    parse_config(ctx, new, context);
+    if (ctx->has_errors) {
+        context->has_errors = true;
+    }
 
-    extract_workspace_names_from_bindings();
     check_for_duplicate_bindings(context);
-    reorder_bindings();
 
-    if (use_nagbar && (context->has_errors || context->has_warnings || invalid_sets)) {
+    if (ctx->use_nagbar && (context->has_errors || context->has_warnings || invalid_sets)) {
         ELOG("FYI: You are using i3 version %s\n", i3_version);
         if (version == 3)
             ELOG("Please convert your configfile first, then fix any remaining errors (see above).\n");
@@ -1108,22 +1101,22 @@ bool parse_file(const char *f, bool use_nagbar) {
         start_config_error_nagbar(f, context->has_errors || invalid_sets);
     }
 
-    bool has_errors = context->has_errors;
+    const bool has_errors = context->has_errors;
 
     FREE(context->line_copy);
     free(context);
     free(new);
     free(buf);
 
-    while (!SLIST_EMPTY(&variables)) {
-        current = SLIST_FIRST(&variables);
-        FREE(current->key);
-        FREE(current->value);
-        SLIST_REMOVE_HEAD(&variables, variables);
-        FREE(current);
+    if (chdir(old_dir) == -1) {
+        ELOG("chdir(%s) failed: %s\n", old_dir, strerror(errno));
+        return PARSE_FILE_FAILED;
     }
-
-    return !has_errors;
+    free(old_dir);
+    if (has_errors) {
+        return PARSE_FILE_CONFIG_ERRORS;
+    }
+    return PARSE_FILE_SUCCESS;
 }
 
 #endif
diff --git a/src/display_version.c b/src/display_version.c
index 32250c155..bced4c191 100644
--- a/src/display_version.c
+++ b/src/display_version.c
@@ -14,22 +14,34 @@
 #include <time.h>
 #include <unistd.h>
 
-static bool human_readable_key, loaded_config_file_name_key;
-static char *human_readable_version, *loaded_config_file_name;
+static bool human_readable_key;
+static bool loaded_config_file_name_key;
+static bool included_config_file_names;
+
+static char *human_readable_version;
+static char *loaded_config_file_name;
 
 static int version_string(void *ctx, const unsigned char *val, size_t len) {
-    if (human_readable_key)
+    if (human_readable_key) {
         sasprintf(&human_readable_version, "%.*s", (int)len, val);
-    if (loaded_config_file_name_key)
+    }
+    if (loaded_config_file_name_key) {
         sasprintf(&loaded_config_file_name, "%.*s", (int)len, val);
+    }
+    if (included_config_file_names) {
+        IncludedFile *file = scalloc(1, sizeof(IncludedFile));
+        sasprintf(&(file->path), "%.*s", (int)len, val);
+        TAILQ_INSERT_TAIL(&included_files, file, files);
+    }
     return 1;
 }
 
 static int version_map_key(void *ctx, const unsigned char *stringval, size_t stringlen) {
-    human_readable_key = (stringlen == strlen("human_readable") &&
-                          strncmp((const char *)stringval, "human_readable", strlen("human_readable")) == 0);
-    loaded_config_file_name_key = (stringlen == strlen("loaded_config_file_name") &&
-                                   strncmp((const char *)stringval, "loaded_config_file_name", strlen("loaded_config_file_name")) == 0);
+#define KEY_MATCHES(x) (stringlen == strlen(x) && strncmp((const char *)stringval, x, strlen(x)) == 0)
+    human_readable_key = KEY_MATCHES("human_readable");
+    loaded_config_file_name_key = KEY_MATCHES("loaded_config_file_name");
+    included_config_file_names = KEY_MATCHES("included_config_file_names");
+#undef KEY_MATCHES
     return 1;
 }
 
@@ -38,6 +50,22 @@ static yajl_callbacks version_callbacks = {
     .yajl_map_key = version_map_key,
 };
 
+static void print_config_path(const char *path, const char *role) {
+    struct stat sb;
+    time_t now;
+    char mtime[64];
+
+    printf("  %s (%s)", path, role);
+    if (stat(path, &sb) == -1) {
+        printf("\n");
+        ELOG("Cannot stat config file \"%s\"\n", path);
+    } else {
+        strftime(mtime, sizeof(mtime), "%c", localtime(&(sb.st_mtime)));
+        time(&now);
+        printf(" (last modified: %s, %.f seconds ago)\n", mtime, difftime(now, sb.st_mtime));
+    }
+}
+
 /*
  * Connects to i3 to find out the currently running version. Useful since it
  * might be different from the version compiled into this binary (maybe the
@@ -98,17 +126,11 @@ void display_running_version(void) {
     printf("Running i3 version: %s (pid %s)\n", human_readable_version, pid_from_atom);
 
     if (loaded_config_file_name) {
-        struct stat sb;
-        time_t now;
-        char mtime[64];
-        printf("Loaded i3 config: %s", loaded_config_file_name);
-        if (stat(loaded_config_file_name, &sb) == -1) {
-            printf("\n");
-            ELOG("Cannot stat config file \"%s\"\n", loaded_config_file_name);
-        } else {
-            strftime(mtime, sizeof(mtime), "%c", localtime(&(sb.st_mtime)));
-            time(&now);
-            printf(" (Last modified: %s, %.f seconds ago)\n", mtime, difftime(now, sb.st_mtime));
+        printf("Loaded i3 config:\n");
+        print_config_path(loaded_config_file_name, "main");
+        IncludedFile *file;
+        TAILQ_FOREACH (file, &included_files, files) {
+            print_config_path(file->path, "included");
         }
     }
 
diff --git a/src/ewmh.c b/src/ewmh.c
index c61fb5f39..ba91093db 100644
--- a/src/ewmh.c
+++ b/src/ewmh.c
@@ -278,10 +278,10 @@ void ewmh_update_client_list_stacking(xcb_window_t *stack, int num_windows) {
  */
 void ewmh_update_sticky(xcb_window_t window, bool sticky) {
     if (sticky) {
-        DLOG("Setting _NET_WM_STATE_STICKY for window = %d.\n", window);
+        DLOG("Setting _NET_WM_STATE_STICKY for window = %08x.\n", window);
         xcb_add_property_atom(conn, window, A__NET_WM_STATE, A__NET_WM_STATE_STICKY);
     } else {
-        DLOG("Removing _NET_WM_STATE_STICKY for window = %d.\n", window);
+        DLOG("Removing _NET_WM_STATE_STICKY for window = %08x.\n", window);
         xcb_remove_property_atom(conn, window, A__NET_WM_STATE, A__NET_WM_STATE_STICKY);
     }
 }
@@ -292,10 +292,10 @@ void ewmh_update_sticky(xcb_window_t window, bool sticky) {
  */
 void ewmh_update_focused(xcb_window_t window, bool is_focused) {
     if (is_focused) {
-        DLOG("Setting _NET_WM_STATE_FOCUSED for window = %d.\n", window);
+        DLOG("Setting _NET_WM_STATE_FOCUSED for window = %08x.\n", window);
         xcb_add_property_atom(conn, window, A__NET_WM_STATE, A__NET_WM_STATE_FOCUSED);
     } else {
-        DLOG("Removing _NET_WM_STATE_FOCUSED for window = %d.\n", window);
+        DLOG("Removing _NET_WM_STATE_FOCUSED for window = %08x.\n", window);
         xcb_remove_property_atom(conn, window, A__NET_WM_STATE, A__NET_WM_STATE_FOCUSED);
     }
 }
diff --git a/src/handlers.c b/src/handlers.c
index 5cffea1d9..884eaf2d5 100644
--- a/src/handlers.c
+++ b/src/handlers.c
@@ -818,12 +818,12 @@ static void handle_client_message(xcb_client_message_event_t *event) {
         if (event->data.data32[0] == XCB_ICCCM_WM_STATE_ICONIC) {
             /* For compatiblity reasons, Wine will request iconic state and cannot ensure that the WM has agreed on it;
              * immediately revert to normal to avoid being stuck in a paused state. */
-            DLOG("Client has requested iconic state, rejecting. (window = %d)\n", event->window);
+            DLOG("Client has requested iconic state, rejecting. (window = %08x)\n", event->window);
             long data[] = {XCB_ICCCM_WM_STATE_NORMAL, XCB_NONE};
             xcb_change_property(conn, XCB_PROP_MODE_REPLACE, event->window,
                                 A_WM_STATE, A_WM_STATE, 32, 2, data);
         } else {
-            DLOG("Not handling WM_CHANGE_STATE request. (window = %d, state = %d)\n", event->window, event->data.data32[0]);
+            DLOG("Not handling WM_CHANGE_STATE request. (window = %08x, state = %d)\n", event->window, event->data.data32[0]);
         }
     } else if (event->type == A__NET_CURRENT_DESKTOP) {
         /* This request is used by pagers and bars to change the current
@@ -891,7 +891,7 @@ static void handle_client_message(xcb_client_message_event_t *event) {
             tree_close_internal(con, KILL_WINDOW, false);
             tree_render();
         } else {
-            DLOG("Couldn't find con for _NET_CLOSE_WINDOW request. (window = %d)\n", event->window);
+            DLOG("Couldn't find con for _NET_CLOSE_WINDOW request. (window = %08x)\n", event->window);
         }
     } else if (event->type == A__NET_WM_MOVERESIZE) {
         /*
@@ -900,7 +900,7 @@ static void handle_client_message(xcb_client_message_event_t *event) {
          */
         Con *con = con_by_window_id(event->window);
         if (!con || !con_is_floating(con)) {
-            DLOG("Couldn't find con for _NET_WM_MOVERESIZE request, or con not floating (window = %d)\n", event->window);
+            DLOG("Couldn't find con for _NET_WM_MOVERESIZE request, or con not floating (window = %08x)\n", event->window);
             return;
         }
         DLOG("Handling _NET_WM_MOVERESIZE request (con = %p)\n", con);
@@ -1073,6 +1073,76 @@ static void handle_focus_in(xcb_focus_in_event_t *event) {
     tree_render();
 }
 
+/*
+ * Log FocusOut events.
+ *
+ */
+static void handle_focus_out(xcb_focus_in_event_t *event) {
+    Con *con = con_by_window_id(event->event);
+    const char *window_name, *mode, *detail;
+
+    if (con != NULL) {
+        window_name = con->name;
+        if (window_name == NULL) {
+            window_name = "<unnamed con>";
+        }
+    } else if (event->event == root) {
+        window_name = "<the root window>";
+    } else {
+        window_name = "<unknown window>";
+    }
+
+    switch (event->mode) {
+        case XCB_NOTIFY_MODE_NORMAL:
+            mode = "Normal";
+            break;
+        case XCB_NOTIFY_MODE_GRAB:
+            mode = "Grab";
+            break;
+        case XCB_NOTIFY_MODE_UNGRAB:
+            mode = "Ungrab";
+            break;
+        case XCB_NOTIFY_MODE_WHILE_GRABBED:
+            mode = "WhileGrabbed";
+            break;
+        default:
+            mode = "<unknown>";
+            break;
+    }
+
+    switch (event->detail) {
+        case XCB_NOTIFY_DETAIL_ANCESTOR:
+            detail = "Ancestor";
+            break;
+        case XCB_NOTIFY_DETAIL_VIRTUAL:
+            detail = "Virtual";
+            break;
+        case XCB_NOTIFY_DETAIL_INFERIOR:
+            detail = "Inferior";
+            break;
+        case XCB_NOTIFY_DETAIL_NONLINEAR:
+            detail = "Nonlinear";
+            break;
+        case XCB_NOTIFY_DETAIL_NONLINEAR_VIRTUAL:
+            detail = "NonlinearVirtual";
+            break;
+        case XCB_NOTIFY_DETAIL_POINTER:
+            detail = "Pointer";
+            break;
+        case XCB_NOTIFY_DETAIL_POINTER_ROOT:
+            detail = "PointerRoot";
+            break;
+        case XCB_NOTIFY_DETAIL_NONE:
+            detail = "NONE";
+            break;
+        default:
+            detail = "unknown";
+            break;
+    }
+
+    DLOG("focus change out: window 0x%08x (con %p, %s) lost focus with detail=%s, mode=%s\n", event->event, con, window_name, detail, mode);
+}
+
 /*
  * Handles ConfigureNotify events for the root window, which are generated when
  * the monitor configuration changed.
@@ -1089,6 +1159,23 @@ static void handle_configure_notify(xcb_configure_notify_event_t *event) {
         return;
     }
     randr_query_outputs();
+
+    ipc_send_event("output", I3_IPC_EVENT_OUTPUT, "{\"change\":\"unspecified\"}");
+}
+
+/*
+ * Handles SelectionClear events for the root window, which are generated when
+ * we lose ownership of a selection.
+ */
+static void handle_selection_clear(xcb_selection_clear_event_t *event) {
+    if (event->selection != wm_sn) {
+        DLOG("SelectionClear for unknown selection %d, ignoring\n", event->selection);
+        return;
+    }
+    LOG("Lost WM_Sn selection, exiting.\n");
+    exit(EXIT_SUCCESS);
+
+    /* unreachable */
 }
 
 /*
@@ -1101,6 +1188,16 @@ static bool handle_class_change(Con *con, xcb_get_property_reply_t *prop) {
     return true;
 }
 
+/*
+ * Handles the WM_CLIENT_MACHINE property for assignments and criteria selection.
+ *
+ */
+static bool handle_machine_change(Con *con, xcb_get_property_reply_t *prop) {
+    window_update_machine(con->window, prop);
+    con = remanage_window(con);
+    return true;
+}
+
 /*
  * Handles the _MOTIF_WM_HINTS property of specifing window deocration settings.
  *
@@ -1190,6 +1287,14 @@ static bool handle_i3_floating(Con *con, xcb_get_property_reply_t *prop) {
     return true;
 }
 
+static bool handle_windowicon_change(Con *con, xcb_get_property_reply_t *prop) {
+    window_update_icon(con->window, prop);
+
+    x_push_changes(croot);
+
+    return true;
+}
+
 /* Returns false if the event could not be processed (e.g. the window could not
  * be found), true otherwise */
 typedef bool (*cb_property_handler_t)(Con *con, xcb_get_property_reply_t *property);
@@ -1212,7 +1317,9 @@ static struct property_handler_t property_handlers[] = {
     {0, UINT_MAX, handle_strut_partial_change},
     {0, UINT_MAX, handle_window_type},
     {0, UINT_MAX, handle_i3_floating},
-    {0, 5 * sizeof(uint64_t), handle_motif_hints_change}};
+    {0, 128, handle_machine_change},
+    {0, 5 * sizeof(uint64_t), handle_motif_hints_change},
+    {0, UINT_MAX, handle_windowicon_change}};
 #define NUM_HANDLERS (sizeof(property_handlers) / sizeof(struct property_handler_t))
 
 /*
@@ -1234,7 +1341,9 @@ void property_handlers_init(void) {
     property_handlers[8].atom = A__NET_WM_STRUT_PARTIAL;
     property_handlers[9].atom = A__NET_WM_WINDOW_TYPE;
     property_handlers[10].atom = A_I3_FLOATING_WINDOW;
-    property_handlers[11].atom = A__MOTIF_WM_HINTS;
+    property_handlers[11].atom = XCB_ATOM_WM_CLIENT_MACHINE;
+    property_handlers[12].atom = A__MOTIF_WM_HINTS;
+    property_handlers[13].atom = A__NET_WM_ICON;
 }
 
 static void property_notify(uint8_t state, xcb_window_t window, xcb_atom_t atom) {
@@ -1410,6 +1519,10 @@ void handle_event(int type, xcb_generic_event_t *event) {
             handle_focus_in((xcb_focus_in_event_t *)event);
             break;
 
+        case XCB_FOCUS_OUT:
+            handle_focus_out((xcb_focus_out_event_t *)event);
+            break;
+
         case XCB_PROPERTY_NOTIFY: {
             xcb_property_notify_event_t *e = (xcb_property_notify_event_t *)event;
             last_timestamp = e->time;
@@ -1421,6 +1534,10 @@ void handle_event(int type, xcb_generic_event_t *event) {
             handle_configure_notify((xcb_configure_notify_event_t *)event);
             break;
 
+        case XCB_SELECTION_CLEAR:
+            handle_selection_clear((xcb_selection_clear_event_t *)event);
+            break;
+
         default:
             //DLOG("Unhandled event of type %d\n", type);
             break;
diff --git a/src/ipc.c b/src/ipc.c
index eac4d9b38..147332108 100644
--- a/src/ipc.c
+++ b/src/ipc.c
@@ -27,22 +27,6 @@ char *current_socketpath = NULL;
 
 TAILQ_HEAD(ipc_client_head, ipc_client) all_clients = TAILQ_HEAD_INITIALIZER(all_clients);
 
-/*
- * Puts the given socket file descriptor into non-blocking mode or dies if
- * setting O_NONBLOCK failed. Non-blocking sockets are a good idea for our
- * IPC model because we should by no means block the window manager.
- *
- */
-static void set_nonblock(int sockfd) {
-    int flags = fcntl(sockfd, F_GETFL, 0);
-    if (flags & O_NONBLOCK) {
-        return;
-    }
-    flags |= O_NONBLOCK;
-    if (fcntl(sockfd, F_SETFL, flags) < 0)
-        err(-1, "Could not set O_NONBLOCK");
-}
-
 static void ipc_client_timeout(EV_P_ ev_timer *w, int revents);
 static void ipc_socket_writeable_cb(EV_P_ struct ev_io *w, int revents);
 
@@ -251,9 +235,9 @@ static void dump_rect(yajl_gen gen, const char *name, Rect r) {
     ystr(name);
     y(map_open);
     ystr("x");
-    y(integer, r.x);
+    y(integer, (int32_t)r.x);
     ystr("y");
-    y(integer, r.y);
+    y(integer, (int32_t)r.y);
     ystr("width");
     y(integer, r.width);
     ystr("height");
@@ -536,6 +520,9 @@ void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
         ystr(con->title_format);
     }
 
+    ystr("window_icon_padding");
+    y(integer, con->window_icon_padding);
+
     if (con->type == CT_WORKSPACE) {
         ystr("num");
         y(integer, con->num);
@@ -597,6 +584,7 @@ void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
         DUMP_PROPERTY("class", class_class);
         DUMP_PROPERTY("instance", class_instance);
         DUMP_PROPERTY("window_role", role);
+        DUMP_PROPERTY("machine", machine);
 
         if (con->window->name != NULL) {
             ystr("title");
@@ -686,6 +674,7 @@ void dump_node(yajl_gen gen, struct Con *con, bool inplace_restart) {
         DUMP_REGEX(instance);
         DUMP_REGEX(window_role);
         DUMP_REGEX(title);
+        DUMP_REGEX(machine);
 
 #undef DUMP_REGEX
         y(map_close);
@@ -1083,6 +1072,17 @@ IPC_HANDLER(get_version) {
     ystr("loaded_config_file_name");
     ystr(current_configpath);
 
+    ystr("included_config_file_names");
+    y(array_open);
+    IncludedFile *file;
+    TAILQ_FOREACH (file, &included_files, files) {
+        if (file == TAILQ_FIRST(&included_files)) {
+            /* Skip the first file, which is current_configpath. */
+            continue;
+        }
+        ystr(file->path);
+    }
+    y(array_close);
     y(map_close);
 
     const unsigned char *payload;
@@ -1265,7 +1265,22 @@ IPC_HANDLER(get_config) {
     y(map_open);
 
     ystr("config");
-    ystr(current_config);
+    IncludedFile *file = TAILQ_FIRST(&included_files);
+    ystr(file->raw_contents);
+
+    ystr("included_configs");
+    y(array_open);
+    TAILQ_FOREACH (file, &included_files, files) {
+        y(map_open);
+        ystr("path");
+        ystr(file->path);
+        ystr("raw_contents");
+        ystr(file->raw_contents);
+        ystr("variable_replaced_contents");
+        ystr(file->variable_replaced_contents);
+        y(map_close);
+    }
+    y(array_close);
 
     y(map_close);
 
@@ -1552,57 +1567,6 @@ ipc_client *ipc_new_client_on_fd(EV_P_ int fd) {
     return client;
 }
 
-/*
- * Creates the UNIX domain socket at the given path, sets it to non-blocking
- * mode, bind()s and listen()s on it.
- *
- */
-int ipc_create_socket(const char *filename) {
-    int sockfd;
-
-    FREE(current_socketpath);
-
-    char *resolved = resolve_tilde(filename);
-    DLOG("Creating IPC-socket at %s\n", resolved);
-    char *copy = sstrdup(resolved);
-    const char *dir = dirname(copy);
-    if (!path_exists(dir))
-        mkdirp(dir, DEFAULT_DIR_MODE);
-    free(copy);
-
-    /* Unlink the unix domain socket before */
-    unlink(resolved);
-
-    if ((sockfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
-        perror("socket()");
-        free(resolved);
-        return -1;
-    }
-
-    (void)fcntl(sockfd, F_SETFD, FD_CLOEXEC);
-
-    struct sockaddr_un addr;
-    memset(&addr, 0, sizeof(struct sockaddr_un));
-    addr.sun_family = AF_LOCAL;
-    strncpy(addr.sun_path, resolved, sizeof(addr.sun_path) - 1);
-    if (bind(sockfd, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) < 0) {
-        perror("bind()");
-        free(resolved);
-        return -1;
-    }
-
-    set_nonblock(sockfd);
-
-    if (listen(sockfd, 5) < 0) {
-        perror("listen()");
-        free(resolved);
-        return -1;
-    }
-
-    current_socketpath = resolved;
-    return sockfd;
-}
-
 /*
  * Generates a json workspace event. Returns a dynamically allocated yajl
  * generator. Free with yajl_gen_free().
diff --git a/src/load_layout.c b/src/load_layout.c
index c117f9c6a..9789fb339 100644
--- a/src/load_layout.c
+++ b/src/load_layout.c
@@ -290,6 +290,9 @@ static int json_string(void *ctx, const unsigned char *val, size_t len) {
         } else if (strcasecmp(last_key, "title") == 0) {
             current_swallow->title = regex_new(sval);
             swallow_is_empty = false;
+        } else if (strcasecmp(last_key, "machine") == 0) {
+            current_swallow->machine = regex_new(sval);
+            swallow_is_empty = false;
         } else {
             ELOG("swallow key %s unknown\n", last_key);
         }
@@ -457,6 +460,10 @@ static int json_int(void *ctx, long long val) {
     if (strcasecmp(last_key, "current_border_width") == 0)
         json_node->current_border_width = val;
 
+    if (strcasecmp(last_key, "window_icon_padding") == 0) {
+        json_node->window_icon_padding = val;
+    }
+
     if (strcasecmp(last_key, "depth") == 0)
         json_node->depth = val;
 
diff --git a/src/log.c b/src/log.c
index 326f82b8c..183bb8e63 100644
--- a/src/log.c
+++ b/src/log.c
@@ -12,6 +12,10 @@
 #include "all.h"
 #include "shmlog.h"
 
+#include <ev.h>
+#include <libgen.h>
+#include <sys/socket.h>
+#include <sys/un.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <stdarg.h>
@@ -23,9 +27,6 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <unistd.h>
-#if !defined(__OpenBSD__)
-#include <pthread.h>
-#endif
 
 #if defined(__APPLE__)
 #include <sys/sysctl.h>
@@ -60,6 +61,18 @@ static int logbuffer_shm;
 /* Size (in bytes) of physical memory */
 static long long physical_mem_bytes;
 
+typedef struct log_client {
+    int fd;
+
+    TAILQ_ENTRY(log_client)
+    clients;
+} log_client;
+
+TAILQ_HEAD(log_client_head, log_client)
+log_clients = TAILQ_HEAD_INITIALIZER(log_clients);
+
+void log_broadcast_to_clients(const char *message, size_t len);
+
 /*
  * Writes the offsets for the next write and for the last wrap to the
  * shmlog_header.
@@ -161,14 +174,6 @@ void open_logbuffer(void) {
 
     header = (i3_shmlog_header *)logbuffer;
 
-#if !defined(__OpenBSD__)
-    pthread_condattr_t cond_attr;
-    pthread_condattr_init(&cond_attr);
-    if (pthread_condattr_setpshared(&cond_attr, PTHREAD_PROCESS_SHARED) != 0)
-        fprintf(stderr, "pthread_condattr_setpshared() failed, i3-dump-log -f will not work!\n");
-    pthread_cond_init(&(header->condvar), &cond_attr);
-#endif
-
     logwalk = logbuffer + sizeof(i3_shmlog_header);
     loglastwrap = logbuffer + logbuffer_size;
     store_log_markers();
@@ -283,13 +288,10 @@ static void vlog(const bool print, const char *fmt, va_list args) {
 
         store_log_markers();
 
-#if !defined(__OpenBSD__)
-        /* Wake up all (i3-dump-log) processes waiting for condvar. */
-        pthread_cond_broadcast(&(header->condvar));
-#endif
-
         if (print)
             fwrite(message, len, 1, stdout);
+
+        log_broadcast_to_clients(message, len);
     }
 }
 
@@ -370,3 +372,51 @@ void purge_zerobyte_logfile(void) {
         rmdir(errorfilename);
     }
 }
+
+char *current_log_stream_socket_path = NULL;
+
+/*
+ * Handler for activity on the listening socket, meaning that a new client
+ * has just connected and we should accept() them. Sets up the event handler
+ * for activity on the new connection and inserts the file descriptor into
+ * the list of log clients.
+ *
+ */
+void log_new_client(EV_P_ struct ev_io *w, int revents) {
+    struct sockaddr_un peer;
+    socklen_t len = sizeof(struct sockaddr_un);
+    int fd;
+    if ((fd = accept(w->fd, (struct sockaddr *)&peer, &len)) < 0) {
+        if (errno != EINTR) {
+            perror("accept()");
+        }
+        return;
+    }
+
+    /* Close this file descriptor on exec() */
+    (void)fcntl(fd, F_SETFD, FD_CLOEXEC);
+
+    set_nonblock(fd);
+
+    log_client *client = scalloc(1, sizeof(log_client));
+    client->fd = fd;
+    TAILQ_INSERT_TAIL(&log_clients, client, clients);
+
+    DLOG("log: new client connected on fd %d\n", fd);
+}
+
+void log_broadcast_to_clients(const char *message, size_t len) {
+    log_client *current = TAILQ_FIRST(&log_clients);
+    while (current != TAILQ_END(&log_clients)) {
+        /* XXX: In case slow connections turn out to be a problem here
+         * (unlikely as long as i3-dump-log is the only consumer), introduce
+         * buffering, similar to the IPC interface. */
+        ssize_t n = writeall(current->fd, message, len);
+        log_client *previous = current;
+        current = TAILQ_NEXT(current, clients);
+        if (n < 0) {
+            TAILQ_REMOVE(&log_clients, previous, clients);
+            free(previous);
+        }
+    }
+}
diff --git a/src/main.c b/src/main.c
index 220195597..c73601da6 100644
--- a/src/main.c
+++ b/src/main.c
@@ -24,6 +24,9 @@
 #include <sys/types.h>
 #include <sys/un.h>
 #include <unistd.h>
+#include <xcb/xcb_atom.h>
+#include <xcb/xinerama.h>
+#include <xcb/bigreq.h>
 
 #ifdef I3_ASAN_ENABLED
 #include <sanitizer/lsan_interface.h>
@@ -63,6 +66,9 @@ xcb_timestamp_t last_timestamp = XCB_CURRENT_TIME;
 xcb_screen_t *root_screen;
 xcb_window_t root;
 
+xcb_window_t wm_sn_selection_owner;
+xcb_atom_t wm_sn;
+
 /* Color depth, visual id and colormap to use when creating windows and
  * pixmaps. Will use 32 bit depth and an appropriate visual, if available,
  * otherwise the root window’s default (usually 24 bit TrueColor). */
@@ -181,6 +187,9 @@ static void i3_exit(void) {
     }
     ipc_shutdown(SHUTDOWN_REASON_EXIT, -1);
     unlink(config.ipc_socket_path);
+    if (current_log_stream_socket_path != NULL) {
+        unlink(current_log_stream_socket_path);
+    }
     xcb_disconnect(conn);
 
     /* If a nagbar is active, kill it */
@@ -279,6 +288,7 @@ int main(int argc, char *argv[]) {
     char *fake_outputs = NULL;
     bool disable_signalhandler = false;
     bool only_check_config = false;
+    bool replace_wm = false;
     static struct option long_options[] = {
         {"no-autostart", no_argument, 0, 'a'},
         {"config", required_argument, 0, 'c'},
@@ -301,6 +311,7 @@ int main(int argc, char *argv[]) {
         {"fake_outputs", required_argument, 0, 0},
         {"fake-outputs", required_argument, 0, 0},
         {"force-old-config-parser-v4.4-only", no_argument, 0, 0},
+        {"replace", no_argument, 0, 'r'},
         {0, 0, 0, 0}};
     int option_index = 0, opt;
 
@@ -325,7 +336,7 @@ int main(int argc, char *argv[]) {
 
     start_argv = argv;
 
-    while ((opt = getopt_long(argc, argv, "c:CvmaL:hld:V", long_options, &option_index)) != -1) {
+    while ((opt = getopt_long(argc, argv, "c:CvmaL:hld:Vr", long_options, &option_index)) != -1) {
         switch (opt) {
             case 'a':
                 LOG("Autostart disabled using -a\n");
@@ -363,6 +374,9 @@ int main(int argc, char *argv[]) {
             case 'l':
                 /* DEPRECATED, ignored for the next 3 versions (3.e, 3.f, 3.g) */
                 break;
+            case 'r':
+                replace_wm = true;
+                break;
             case 0:
                 if (strcmp(long_options[option_index].name, "force-xinerama") == 0 ||
                     strcmp(long_options[option_index].name, "force_xinerama") == 0) {
@@ -443,6 +457,9 @@ int main(int argc, char *argv[]) {
                                 "\tThe default is %d bytes.\n",
                         shmlog_size);
                 fprintf(stderr, "\n");
+                fprintf(stderr, "\t--replace\n"
+                                "\tReplace an existing window manager.\n");
+                fprintf(stderr, "\n");
                 fprintf(stderr, "If you pass plain text arguments, i3 will interpret them as a command\n"
                                 "to send to a currently running i3 (like i3-msg). This allows you to\n"
                                 "use nice and logical commands, such as:\n"
@@ -570,6 +587,21 @@ int main(int argc, char *argv[]) {
     root_screen = xcb_aux_get_screen(conn, conn_screen);
     root = root_screen->root;
 
+    /* Prefetch X11 extensions that we are interested in. */
+    xcb_prefetch_extension_data(conn, &xcb_xkb_id);
+    xcb_prefetch_extension_data(conn, &xcb_shape_id);
+    /* BIG-REQUESTS is used by libxcb internally. */
+    xcb_prefetch_extension_data(conn, &xcb_big_requests_id);
+    if (force_xinerama) {
+        xcb_prefetch_extension_data(conn, &xcb_xinerama_id);
+    } else {
+        xcb_prefetch_extension_data(conn, &xcb_randr_id);
+    }
+
+    /* Prepare for us to get a current timestamp as recommended by ICCCM */
+    xcb_change_window_attributes(conn, root, XCB_CW_EVENT_MASK, (uint32_t[]){XCB_EVENT_MASK_PROPERTY_CHANGE});
+    xcb_change_property(conn, XCB_PROP_MODE_APPEND, root, XCB_ATOM_SUPERSCRIPT_X, XCB_ATOM_CARDINAL, 32, 0, "");
+
     /* Place requests for the atoms we need as soon as possible */
 #define xmacro(atom) \
     xcb_intern_atom_cookie_t atom##_cookie = xcb_intern_atom(conn, 0, strlen(#atom), #atom);
@@ -599,6 +631,8 @@ int main(int argc, char *argv[]) {
         visual_type = get_visualtype(root_screen);
     }
 
+    xcb_prefetch_maximum_request_length(conn);
+
     init_dpi();
 
     DLOG("root_depth = %d, visual_id = 0x%08x.\n", root_depth, visual_type->visual_id);
@@ -609,6 +643,22 @@ int main(int argc, char *argv[]) {
     xcb_get_geometry_cookie_t gcookie = xcb_get_geometry(conn, root);
     xcb_query_pointer_cookie_t pointercookie = xcb_query_pointer(conn, root);
 
+    /* Get the PropertyNotify event we caused above */
+    xcb_flush(conn);
+    {
+        xcb_generic_event_t *event;
+        DLOG("waiting for PropertyNotify event\n");
+        while ((event = xcb_wait_for_event(conn)) != NULL) {
+            if (event->response_type == XCB_PROPERTY_NOTIFY) {
+                last_timestamp = ((xcb_property_notify_event_t *)event)->time;
+                free(event);
+                break;
+            }
+            free(event);
+        }
+        DLOG("got timestamp %d\n", last_timestamp);
+    }
+
     /* Setup NetWM atoms */
 #define xmacro(name)                                                                       \
     do {                                                                                   \
@@ -638,6 +688,103 @@ int main(int argc, char *argv[]) {
         force_xinerama = true;
     }
 
+    /* Acquire the WM_Sn selection. */
+    {
+        /* Get the WM_Sn atom */
+        char *atom_name = xcb_atom_name_by_screen("WM_S", conn_screen);
+        wm_sn_selection_owner = xcb_generate_id(conn);
+
+        if (atom_name == NULL) {
+            ELOG("xcb_atom_name_by_screen(\"WM_S\", %d) failed, exiting\n", conn_screen);
+            return 1;
+        }
+
+        xcb_intern_atom_reply_t *atom_reply;
+        atom_reply = xcb_intern_atom_reply(conn,
+                                           xcb_intern_atom_unchecked(conn,
+                                                                     0,
+                                                                     strlen(atom_name),
+                                                                     atom_name),
+                                           NULL);
+        free(atom_name);
+        if (atom_reply == NULL) {
+            ELOG("Failed to intern the WM_Sn atom, exiting\n");
+            return 1;
+        }
+        wm_sn = atom_reply->atom;
+        free(atom_reply);
+
+        /* Check if the selection is already owned */
+        xcb_get_selection_owner_reply_t *selection_reply =
+            xcb_get_selection_owner_reply(conn,
+                                          xcb_get_selection_owner(conn, wm_sn),
+                                          NULL);
+        if (selection_reply && selection_reply->owner != XCB_NONE && !replace_wm) {
+            ELOG("Another window manager is already running (WM_Sn is owned)");
+            return 1;
+        }
+
+        /* Become the selection owner */
+        xcb_create_window(conn,
+                          root_screen->root_depth,
+                          wm_sn_selection_owner, /* window id */
+                          root_screen->root,     /* parent */
+                          -1, -1, 1, 1,          /* geometry */
+                          0,                     /* border width */
+                          XCB_WINDOW_CLASS_INPUT_OUTPUT,
+                          root_screen->root_visual,
+                          0, NULL);
+        xcb_change_property(conn,
+                            XCB_PROP_MODE_REPLACE,
+                            wm_sn_selection_owner,
+                            XCB_ATOM_WM_CLASS,
+                            XCB_ATOM_STRING,
+                            8,
+                            (strlen("i3-WM_Sn") + 1) * 2,
+                            "i3-WM_Sn\0i3-WM_Sn\0");
+
+        xcb_set_selection_owner(conn, wm_sn_selection_owner, wm_sn, last_timestamp);
+
+        if (selection_reply && selection_reply->owner != XCB_NONE) {
+            unsigned int usleep_time = 100000; /* 0.1 seconds */
+            int check_rounds = 150;            /* Wait for a maximum of 15 seconds */
+            xcb_get_geometry_reply_t *geom_reply = NULL;
+
+            DLOG("waiting for old WM_Sn selection owner to exit");
+            do {
+                free(geom_reply);
+                usleep(usleep_time);
+                if (check_rounds-- == 0) {
+                    ELOG("The old window manager is not exiting");
+                    return 1;
+                }
+                geom_reply = xcb_get_geometry_reply(conn,
+                                                    xcb_get_geometry(conn, selection_reply->owner),
+                                                    NULL);
+            } while (geom_reply != NULL);
+        }
+        free(selection_reply);
+
+        /* Announce that we are the new owner */
+        /* Every X11 event is 32 bytes long. Therefore, XCB will copy 32 bytes.
+         * In order to properly initialize these bytes, we allocate 32 bytes even
+         * though we only need less for an xcb_client_message_event_t */
+        union {
+            xcb_client_message_event_t message;
+            char storage[32];
+        } event;
+        memset(&event, 0, sizeof(event));
+        event.message.response_type = XCB_CLIENT_MESSAGE;
+        event.message.window = root_screen->root;
+        event.message.format = 32;
+        event.message.type = A_MANAGER;
+        event.message.data.data32[0] = last_timestamp;
+        event.message.data.data32[1] = wm_sn;
+        event.message.data.data32[2] = wm_sn_selection_owner;
+
+        xcb_send_event(conn, 0, root_screen->root, XCB_EVENT_MASK_STRUCTURE_NOTIFY, event.storage);
+    }
+
     xcb_void_cookie_t cookie;
     cookie = xcb_change_window_attributes_checked(conn, root, XCB_CW_EVENT_MASK, (uint32_t[]){ROOT_EVENT_MASK});
     xcb_generic_error_t *error = xcb_request_check(conn, cookie);
@@ -663,9 +810,6 @@ int main(int argc, char *argv[]) {
     xcursor_set_root_cursor(XCURSOR_CURSOR_POINTER);
 
     const xcb_query_extension_reply_t *extreply;
-    xcb_prefetch_extension_data(conn, &xcb_xkb_id);
-    xcb_prefetch_extension_data(conn, &xcb_shape_id);
-
     extreply = xcb_get_extension_data(conn, &xcb_xkb_id);
     xkb_supported = extreply->present;
     if (!extreply->present) {
@@ -845,7 +989,7 @@ int main(int argc, char *argv[]) {
     tree_render();
 
     /* Create the UNIX domain socket for IPC */
-    int ipc_socket = ipc_create_socket(config.ipc_socket_path);
+    int ipc_socket = create_socket(config.ipc_socket_path, &current_socketpath);
     if (ipc_socket == -1) {
         ELOG("Could not create the IPC socket, IPC disabled\n");
     } else {
@@ -854,9 +998,21 @@ int main(int argc, char *argv[]) {
         ev_io_start(main_loop, ipc_io);
     }
 
-    /* Also handle the UNIX domain sockets passed via socket activation. The
-     * parameter 1 means "remove the environment variables", we don’t want to
-     * pass these to child processes. */
+    /* Chose a file name in /tmp/ based on the PID */
+    char *log_stream_socket_path = get_process_filename("log-stream-socket");
+    int log_socket = create_socket(log_stream_socket_path, &current_log_stream_socket_path);
+    free(log_stream_socket_path);
+    if (log_socket == -1) {
+        ELOG("Could not create the log socket, i3-dump-log -f will not work\n");
+    } else {
+        struct ev_io *log_io = scalloc(1, sizeof(struct ev_io));
+        ev_io_init(log_io, log_new_client, log_socket, EV_READ);
+        ev_io_start(main_loop, log_io);
+    }
+
+    /* Also handle the UNIX domain sockets passed via socket
+     * activation. The parameter 0 means "do not remove the
+     * environment variables", we need to be able to reexec. */
     listen_fds = sd_listen_fds(0);
     if (listen_fds < 0)
         ELOG("socket activation: Error in sd_listen_fds\n");
@@ -950,24 +1106,23 @@ int main(int argc, char *argv[]) {
     xcb_ungrab_server(conn);
 
     if (autostart) {
-        LOG("This is not an in-place restart, copying root window contents to a pixmap\n");
+        /* When the root's window background is set to NONE, that might mean
+         * that old content stays visible when a window is closed. That has
+         * unpleasant effect of "my terminal (does not seem to) close!".
+         *
+         * There does not seem to be an easy way to query for this problem, so
+         * we test for it: Open & close a window and check if the background is
+         * redrawn or the window contents stay visible.
+         */
+        LOG("This is not an in-place restart, checking if a wallpaper is set.\n");
+
         xcb_screen_t *root = xcb_aux_get_screen(conn, conn_screen);
-        uint16_t width = root->width_in_pixels;
-        uint16_t height = root->height_in_pixels;
-        xcb_pixmap_t pixmap = xcb_generate_id(conn);
-        xcb_gcontext_t gc = xcb_generate_id(conn);
-
-        xcb_create_pixmap(conn, root->root_depth, pixmap, root->root, width, height);
-
-        xcb_create_gc(conn, gc, root->root,
-                      XCB_GC_FUNCTION | XCB_GC_PLANE_MASK | XCB_GC_FILL_STYLE | XCB_GC_SUBWINDOW_MODE,
-                      (uint32_t[]){XCB_GX_COPY, ~0, XCB_FILL_STYLE_SOLID, XCB_SUBWINDOW_MODE_INCLUDE_INFERIORS});
-
-        xcb_copy_area(conn, root->root, pixmap, gc, 0, 0, 0, 0, width, height);
-        xcb_change_window_attributes(conn, root->root, XCB_CW_BACK_PIXMAP, (uint32_t[]){pixmap});
-        xcb_flush(conn);
-        xcb_free_gc(conn, gc);
-        xcb_free_pixmap(conn, pixmap);
+        if (is_background_set(conn, root)) {
+            LOG("A wallpaper is set, so no screenshot is necessary.\n");
+        } else {
+            LOG("No wallpaper set, copying root window contents to a pixmap\n");
+            set_screenshot_as_wallpaper(conn, root);
+        }
     }
 
 #if defined(__OpenBSD__)
@@ -1041,5 +1196,6 @@ int main(int argc, char *argv[]) {
      * when calling exit() */
     atexit(i3_exit);
 
+    sd_notify(1, "READY=1");
     ev_loop(main_loop, 0);
 }
diff --git a/src/manage.c b/src/manage.c
index e3ea59b6c..3c8ebc8a7 100644
--- a/src/manage.c
+++ b/src/manage.c
@@ -116,7 +116,10 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
         utf8_title_cookie, title_cookie,
         class_cookie, leader_cookie, transient_cookie,
         role_cookie, startup_id_cookie, wm_hints_cookie,
-        wm_normal_hints_cookie, motif_wm_hints_cookie, wm_user_time_cookie, wm_desktop_cookie;
+        wm_normal_hints_cookie, motif_wm_hints_cookie, wm_user_time_cookie, wm_desktop_cookie,
+        wm_machine_cookie;
+
+    xcb_get_property_cookie_t wm_icon_cookie;
 
     geomc = xcb_get_geometry(conn, d);
 
@@ -189,6 +192,8 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
     motif_wm_hints_cookie = GET_PROPERTY(A__MOTIF_WM_HINTS, 5 * sizeof(uint64_t));
     wm_user_time_cookie = GET_PROPERTY(A__NET_WM_USER_TIME, UINT32_MAX);
     wm_desktop_cookie = GET_PROPERTY(A__NET_WM_DESKTOP, UINT32_MAX);
+    wm_machine_cookie = GET_PROPERTY(XCB_ATOM_WM_CLIENT_MACHINE, UINT32_MAX);
+    wm_icon_cookie = GET_PROPERTY(A__NET_WM_ICON, UINT32_MAX);
 
     i3Window *cwindow = scalloc(1, sizeof(i3Window));
     cwindow->id = window;
@@ -202,6 +207,7 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
     window_update_class(cwindow, xcb_get_property_reply(conn, class_cookie, NULL));
     window_update_name_legacy(cwindow, xcb_get_property_reply(conn, title_cookie, NULL));
     window_update_name(cwindow, xcb_get_property_reply(conn, utf8_title_cookie, NULL));
+    window_update_icon(cwindow, xcb_get_property_reply(conn, wm_icon_cookie, NULL));
     window_update_leader(cwindow, xcb_get_property_reply(conn, leader_cookie, NULL));
     window_update_transient_for(cwindow, xcb_get_property_reply(conn, transient_cookie, NULL));
     window_update_strut_partial(cwindow, xcb_get_property_reply(conn, strut_cookie, NULL));
@@ -211,6 +217,7 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
     border_style_t motif_border_style = BS_NORMAL;
     window_update_motif_hints(cwindow, xcb_get_property_reply(conn, motif_wm_hints_cookie, NULL), &motif_border_style);
     window_update_normal_hints(cwindow, xcb_get_property_reply(conn, wm_normal_hints_cookie, NULL), geom);
+    window_update_machine(cwindow, xcb_get_property_reply(conn, wm_machine_cookie, NULL));
     xcb_get_property_reply_t *type_reply = xcb_get_property_reply(conn, wm_type_cookie, NULL);
     xcb_get_property_reply_t *state_reply = xcb_get_property_reply(conn, state_cookie, NULL);
 
diff --git a/src/match.c b/src/match.c
index 6ac312e5d..34314e256 100644
--- a/src/match.c
+++ b/src/match.c
@@ -47,12 +47,14 @@ bool match_is_empty(Match *match) {
             match->instance == NULL &&
             match->window_role == NULL &&
             match->workspace == NULL &&
+            match->machine == NULL &&
             match->urgent == U_DONTCHECK &&
             match->id == XCB_NONE &&
             match->window_type == UINT32_MAX &&
             match->con_id == NULL &&
             match->dock == M_NODOCK &&
-            match->window_mode == WM_ANY);
+            match->window_mode == WM_ANY &&
+            match->match_all_windows == false);
 }
 
 /*
@@ -130,6 +132,8 @@ bool match_matches_window(Match *match, i3Window *window) {
         }
     }
 
+    CHECK_WINDOW_FIELD(machine, machine, str);
+
     Con *con = NULL;
     if (match->urgent == U_LATEST) {
         /* if the window isn't urgent, no sense in searching */
@@ -257,6 +261,10 @@ bool match_matches_window(Match *match, i3Window *window) {
         LOG("window_mode matches\n");
     }
 
+    /* NOTE: See the comment regarding 'all' in match_parse_property()
+     * for an explanation of why match_all_windows isn't explicitly
+     * checked. */
+
     return true;
 }
 
@@ -273,6 +281,7 @@ void match_free(Match *match) {
     regex_free(match->mark);
     regex_free(match->window_role);
     regex_free(match->workspace);
+    regex_free(match->machine);
 }
 
 /*
@@ -390,6 +399,12 @@ void match_parse_property(Match *match, const char *ctype, const char *cvalue) {
         return;
     }
 
+    if (strcmp(ctype, "machine") == 0) {
+        regex_free(match->machine);
+        match->machine = regex_new(cvalue);
+        return;
+    }
+
     if (strcmp(ctype, "tiling") == 0) {
         match->window_mode = WM_TILING;
         return;
@@ -428,5 +443,16 @@ void match_parse_property(Match *match, const char *ctype, const char *cvalue) {
         return;
     }
 
+    /* match_matches_window() only checks negatively, so match_all_windows
+     * won't actually be used there, but that's OK because if no negative
+     * match is found (e.g. because of a more restrictive criterion) the
+     * return value of match_matches_window() is true.
+     * Setting it here only serves to cause match_is_empty() to return false,
+     * otherwise empty criteria rules apply, and that's not what we want. */
+    if (strcmp(ctype, "all") == 0) {
+        match->match_all_windows = true;
+        return;
+    }
+
     ELOG("Unknown criterion: %s\n", ctype);
 }
diff --git a/src/restore_layout.c b/src/restore_layout.c
index c51bfcbe3..6f35d1653 100644
--- a/src/restore_layout.c
+++ b/src/restore_layout.c
@@ -134,7 +134,6 @@ static void update_placeholder_contents(placeholder_state *state) {
     draw_util_clear_surface(&(state->surface), background);
 
     // TODO: make i3font functions per-connection, at least these two for now…?
-    xcb_flush(restore_conn);
     xcb_aux_sync(restore_conn);
 
     Match *swallows;
@@ -153,6 +152,7 @@ static void update_placeholder_contents(placeholder_state *state) {
         APPEND_REGEX(instance);
         APPEND_REGEX(window_role);
         APPEND_REGEX(title);
+        APPEND_REGEX(machine);
 
         if (serialized == NULL) {
             DLOG("This swallows specification is not serializable?!\n");
@@ -179,7 +179,6 @@ static void update_placeholder_contents(placeholder_state *state) {
     int y = (state->rect.height / 2) - (config.font.height / 2);
     draw_util_text(line, &(state->surface), foreground, background, x, y, text_width);
     i3string_free(line);
-    xcb_flush(restore_conn);
     xcb_aux_sync(restore_conn);
 }
 
diff --git a/src/util.c b/src/util.c
index cf7f41c8a..f2c562228 100644
--- a/src/util.c
+++ b/src/util.c
@@ -176,15 +176,6 @@ void exec_i3_utility(char *name, char *argv[]) {
     _exit(2);
 }
 
-/*
- * Checks if the given path exists by calling stat().
- *
- */
-bool path_exists(const char *path) {
-    struct stat buf;
-    return (stat(path, &buf) == 0);
-}
-
 /*
  * Goes through the list of arguments (for exec()) and add/replace the given option,
  * including the option name, its argument, and the option character.
diff --git a/src/window.c b/src/window.c
index bee3fa668..734a3264b 100644
--- a/src/window.c
+++ b/src/window.c
@@ -18,7 +18,10 @@
 void window_free(i3Window *win) {
     FREE(win->class_class);
     FREE(win->class_instance);
+    FREE(win->role);
+    FREE(win->machine);
     i3string_free(win->name);
+    cairo_surface_destroy(win->icon);
     FREE(win->ran_assignments);
     FREE(win);
 }
@@ -466,3 +469,130 @@ void window_update_motif_hints(i3Window *win, xcb_get_property_reply_t *prop, bo
 #undef MWM_DECOR_BORDER
 #undef MWM_DECOR_TITLE
 }
+
+/*
+ * Updates the WM_CLIENT_MACHINE
+ *
+ */
+void window_update_machine(i3Window *win, xcb_get_property_reply_t *prop) {
+    if (prop == NULL || xcb_get_property_value_length(prop) == 0) {
+        DLOG("WM_CLIENT_MACHINE not set.\n");
+        FREE(prop);
+        return;
+    }
+
+    FREE(win->machine);
+    win->machine = sstrndup((char *)xcb_get_property_value(prop), xcb_get_property_value_length(prop));
+    LOG("WM_CLIENT_MACHINE changed to \"%s\"\n", win->machine);
+
+    free(prop);
+}
+
+void window_update_icon(i3Window *win, xcb_get_property_reply_t *prop) {
+    uint32_t *data = NULL;
+    uint32_t width, height;
+    uint64_t len = 0;
+    const uint32_t pref_size = (uint32_t)(render_deco_height() - logical_px(2));
+
+    if (!prop || prop->type != XCB_ATOM_CARDINAL || prop->format != 32) {
+        DLOG("_NET_WM_ICON is not set\n");
+        FREE(prop);
+        return;
+    }
+
+    uint32_t prop_value_len = xcb_get_property_value_length(prop);
+    uint32_t *prop_value = (uint32_t *)xcb_get_property_value(prop);
+
+    /* Find an icon matching the preferred size.
+     * If there is no such icon, take the smallest icon having at least
+     * the preferred size.
+     * If all icons are smaller than the preferred size, chose the largest.
+     */
+    while (prop_value_len > (sizeof(uint32_t) * 2) && prop_value &&
+           prop_value[0] && prop_value[1]) {
+        const uint32_t cur_width = prop_value[0];
+        const uint32_t cur_height = prop_value[1];
+        /* Check that the property is as long as it should be (in bytes),
+           handling integer overflow. "+2" to handle the width and height
+           fields. */
+        const uint64_t cur_len = cur_width * (uint64_t)cur_height;
+        const uint64_t expected_len = (cur_len + 2) * 4;
+
+        if (expected_len > prop_value_len) {
+            break;
+        }
+
+        DLOG("Found _NET_WM_ICON of size: (%d,%d)\n", cur_width, cur_height);
+
+        const bool at_least_preferred_size = (cur_width >= pref_size &&
+                                              cur_height >= pref_size);
+        const bool smaller_than_current = (cur_width < width ||
+                                           cur_height < height);
+        const bool larger_than_current = (cur_width > width ||
+                                          cur_height > height);
+        const bool not_yet_at_preferred = (width < pref_size ||
+                                           height < pref_size);
+        if (len == 0 ||
+            (at_least_preferred_size &&
+             (smaller_than_current || not_yet_at_preferred)) ||
+            (!at_least_preferred_size &&
+             not_yet_at_preferred &&
+             larger_than_current)) {
+            len = cur_len;
+            width = cur_width;
+            height = cur_height;
+            data = prop_value;
+        }
+
+        if (width == pref_size && height == pref_size) {
+            break;
+        }
+
+        /* Find pointer to next icon in the reply. */
+        prop_value_len -= expected_len;
+        prop_value = (uint32_t *)(((uint8_t *)prop_value) + expected_len);
+    }
+
+    if (!data) {
+        DLOG("Could not get _NET_WM_ICON\n");
+        FREE(prop);
+        return;
+    }
+
+    DLOG("Using icon of size (%d,%d) (preferred size: %d)\n",
+         width, height, pref_size);
+
+    win->name_x_changed = true; /* trigger a redraw */
+
+    uint32_t *icon = smalloc(len * 4);
+
+    for (uint64_t i = 0; i < len; i++) {
+        uint8_t r, g, b, a;
+        const uint32_t pixel = data[2 + i];
+        a = (pixel >> 24) & 0xff;
+        r = (pixel >> 16) & 0xff;
+        g = (pixel >> 8) & 0xff;
+        b = (pixel >> 0) & 0xff;
+
+        /* Cairo uses premultiplied alpha */
+        r = (r * a) / 0xff;
+        g = (g * a) / 0xff;
+        b = (b * a) / 0xff;
+
+        icon[i] = ((uint32_t)a << 24) | (r << 16) | (g << 8) | b;
+    }
+
+    if (win->icon != NULL) {
+        cairo_surface_destroy(win->icon);
+    }
+    win->icon = cairo_image_surface_create_for_data(
+        (unsigned char *)icon,
+        CAIRO_FORMAT_ARGB32,
+        width,
+        height,
+        width * 4);
+    static cairo_user_data_key_t free_data;
+    cairo_surface_set_user_data(win->icon, &free_data, icon, free);
+
+    FREE(prop);
+}
diff --git a/src/workspace.c b/src/workspace.c
index e77d544b7..526a2bf70 100644
--- a/src/workspace.c
+++ b/src/workspace.c
@@ -139,7 +139,7 @@ Con *workspace_get(const char *num) {
 
     /* We set workspace->num to the number if this workspace’s name begins with
      * a positive number. Otherwise it’s a named ws and num will be 1. */
-    const long parsed_num = ws_name_to_number(num);
+    const int parsed_num = ws_name_to_number(num);
 
     struct Workspace_Assignment *assignment;
     TAILQ_FOREACH (assignment, &ws_assignments, ws_assignments) {
@@ -254,7 +254,6 @@ void extract_workspace_names_from_bindings(void) {
  */
 Con *create_workspace_on_output(Output *output, Con *content) {
     /* add a workspace to this output */
-    char *name;
     bool exists = true;
     Con *ws = con_new(NULL, NULL);
     ws->type = CT_WORKSPACE;
@@ -270,13 +269,16 @@ Con *create_workspace_on_output(Output *output, Con *content) {
             continue;
         }
 
-        exists = (get_existing_workspace_by_name(target_name) != NULL);
+        const int num = ws_name_to_number(target_name);
+        exists = (num == -1)
+                     ? get_existing_workspace_by_name(target_name)
+                     : get_existing_workspace_by_num(num);
         if (!exists) {
             ws->name = sstrdup(target_name);
             /* Set ->num to the number of the workspace, if the name actually
              * is a number or starts with a number */
-            ws->num = ws_name_to_number(ws->name);
-            LOG("Used number %d for workspace with name %s\n", ws->num, ws->name);
+            ws->num = num;
+            DLOG("Used number %d for workspace with name %s\n", ws->num, ws->name);
 
             break;
         }
@@ -306,6 +308,7 @@ Con *create_workspace_on_output(Output *output, Con *content) {
 
     con_attach(ws, content, false);
 
+    char *name;
     sasprintf(&name, "[i3 con] workspace %s", ws->name);
     x_set_name(ws, name);
     free(name);
@@ -1012,14 +1015,14 @@ void workspace_move_to_output(Con *ws, Output *output) {
         bool used_assignment = false;
         struct Workspace_Assignment *assignment;
         TAILQ_FOREACH (assignment, &ws_assignments, ws_assignments) {
-            bool attached;
-            int num;
             if (!output_triggers_assignment(current_output, assignment)) {
                 continue;
             }
             /* check if this workspace's name or num is already attached to the tree */
-            num = ws_name_to_number(assignment->name);
-            attached = ((num == -1) ? get_existing_workspace_by_name(assignment->name) : get_existing_workspace_by_num(num)) != NULL;
+            const int num = ws_name_to_number(assignment->name);
+            const bool attached = (num == -1)
+                                      ? get_existing_workspace_by_name(assignment->name)
+                                      : get_existing_workspace_by_num(num);
             if (attached) {
                 continue;
             }
diff --git a/src/x.c b/src/x.c
index 80e8efd0d..2401e5336 100644
--- a/src/x.c
+++ b/src/x.c
@@ -539,6 +539,9 @@ void x_draw_decoration(Con *con) {
 
     /* 2: draw the client.background, but only for the parts around the window_rect */
     if (con->window != NULL) {
+        /* Clear visible windows before beginning to draw */
+        draw_util_clear_surface(&(con->frame_buffer), (color_t){.red = 0.0, .green = 0.0, .blue = 0.0});
+
         /* top area */
         draw_util_rectangle(&(con->frame_buffer), config.client.background,
                             0, 0, r->width, w->y);
@@ -611,11 +614,14 @@ void x_draw_decoration(Con *con) {
     /* 5: draw title border */
     x_draw_title_border(con, p);
 
-    /* 6: draw the title */
+    /* 6: draw the icon and title */
     int text_offset_y = (con->deco_rect.height - config.font.height) / 2;
 
-    const int title_padding = logical_px(2);
+    struct Window *win = con->window;
+
     const int deco_width = (int)con->deco_rect.width;
+    const int title_padding = logical_px(2);
+
     int mark_width = 0;
     if (config.show_marks && !TAILQ_EMPTY(&(con->marks_head))) {
         char *formatted_mark = sstrdup("");
@@ -654,7 +660,6 @@ void x_draw_decoration(Con *con) {
     }
 
     i3String *title = NULL;
-    struct Window *win = con->window;
     if (win == NULL) {
         if (con->title_format == NULL) {
             char *_title;
@@ -674,25 +679,45 @@ void x_draw_decoration(Con *con) {
         goto copy_pixmaps;
     }
 
+    /* icon_padding is applied horizontally only, the icon will always use all
+     * available vertical space. */
+    int icon_size = max(0, con->deco_rect.height - logical_px(2));
+    int icon_padding = logical_px(max(1, con->window_icon_padding));
+    int total_icon_space = icon_size + 2 * icon_padding;
+    const bool has_icon = (con->window_icon_padding > -1) && win && win->icon && (total_icon_space < deco_width);
+    if (!has_icon) {
+        icon_size = icon_padding = total_icon_space = 0;
+    }
+    /* Determine x offsets according to title alignment */
+    int icon_offset_x;
     int title_offset_x;
     switch (config.title_align) {
         case ALIGN_LEFT:
-            /* (pad)[text    ](pad)[mark + its pad) */
-            title_offset_x = title_padding;
+            /* (pad)[(pad)(icon)(pad)][text    ](pad)[mark + its pad)
+             *             ^           ^--- title_offset_x
+             *             ^--- icon_offset_x */
+            icon_offset_x = icon_padding;
+            title_offset_x = title_padding + total_icon_space;
             break;
         case ALIGN_CENTER:
-            /* (pad)[  text  ](pad)[mark + its pad)
-             * To center the text inside its allocated space, the surface
-             * between the brackets, we use the formula
-             * (surface_width - predict_text_width) / 2
-             * where surface_width = deco_width - 2 * pad - mark_width
-             * so, offset = pad + (surface_width - predict_text_width) / 2 =
-             * = … = (deco_width - mark_width - predict_text_width) / 2 */
-            title_offset_x = max(title_padding, (deco_width - mark_width - predict_text_width(title)) / 2);
+            /* (pad)[  ][(pad)(icon)(pad)][text  ](pad)[mark + its pad)
+             *                 ^           ^--- title_offset_x
+             *                 ^--- icon_offset_x
+             * Text should come right after the icon (+padding). We calculate
+             * the offset for the icon (white space in the title) by dividing
+             * by two the total available area. That's the decoration width
+             * minus the elements that come after icon_offset_x (icon, its
+             * padding, text, marks). */
+            icon_offset_x = max(icon_padding, (deco_width - icon_padding - icon_size - predict_text_width(title) - title_padding - mark_width) / 2);
+            title_offset_x = max(title_padding, icon_offset_x + icon_padding + icon_size);
             break;
         case ALIGN_RIGHT:
-            /* [mark + its pad](pad)[    text](pad) */
-            title_offset_x = max(title_padding + mark_width, deco_width - title_padding - predict_text_width(title));
+            /* [mark + its pad](pad)[    text][(pad)(icon)(pad)](pad)
+             *                           ^           ^--- icon_offset_x
+             *                           ^--- title_offset_x */
+            title_offset_x = max(title_padding + mark_width, deco_width - title_padding - predict_text_width(title) - total_icon_space);
+            /* Make sure the icon does not escape title boundaries */
+            icon_offset_x = min(deco_width - icon_size - icon_padding - title_padding, title_offset_x + predict_text_width(title) + icon_padding);
             break;
     }
 
@@ -700,7 +725,16 @@ void x_draw_decoration(Con *con) {
                    p->color->text, p->color->background,
                    con->deco_rect.x + title_offset_x,
                    con->deco_rect.y + text_offset_y,
-                   deco_width - mark_width - 2 * title_padding);
+                   deco_width - mark_width - 2 * title_padding - total_icon_space);
+    if (has_icon) {
+        draw_util_image(
+            win->icon,
+            &(parent->frame_buffer),
+            con->deco_rect.x + icon_offset_x,
+            con->deco_rect.y + logical_px(1),
+            icon_size,
+            icon_size);
+    }
 
     if (win == NULL || con->title_format != NULL) {
         I3STRING_FREE(title);
@@ -1426,6 +1460,8 @@ void x_set_i3_atoms(void) {
     xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A_I3_PID, XCB_ATOM_CARDINAL, 32, 1, &pid);
     xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A_I3_CONFIG_PATH, A_UTF8_STRING, 8,
                         strlen(current_configpath), current_configpath);
+    xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A_I3_LOG_STREAM_SOCKET_PATH, A_UTF8_STRING, 8,
+                        strlen(current_log_stream_socket_path), current_log_stream_socket_path);
     update_shmlog_atom();
 }
 
diff --git a/testcases/lib/i3test.pm.in b/testcases/lib/i3test.pm.in
index aedaa6017..0f5252a67 100644
--- a/testcases/lib/i3test.pm.in
+++ b/testcases/lib/i3test.pm.in
@@ -410,7 +410,7 @@ Returns the name of the output on which this workspace resides
 
   cmd 'focus output fake-1';
   cmd 'workspace 1';
-  is(get_output_for_workspace('1', 'fake-0', 'Workspace 1 in output fake-0');
+  is(get_output_for_workspace('1'), 'fake-0', 'Workspace 1 in output fake-0');
 
 =cut
 sub get_output_for_workspace {
@@ -419,10 +419,12 @@ sub get_output_for_workspace {
     my $tree = $i3->get_tree->recv;
     my @outputs = @{$tree->{nodes}};
 
-    foreach (grep { not $_->{name} =~ /^__/ } @outputs) {
-        my $output = $_->{name};
-        foreach (grep { $_->{name} =~ "content" } @{$_->{nodes}}) {
-            return $output if $_->{nodes}[0]->{name} =~ $ws_name;
+    for my $output (@outputs) {
+        next if $output->{name} eq '__i3';
+        # get the first CT_CON of each output
+        my $content = first { $_->{type} eq 'con' } @{$output->{nodes}};
+        if (grep {$_->{name} eq $ws_name} @{$content->{nodes}}){
+            return $output->{name};
         }
     }
 }
diff --git a/testcases/t/116-nestedcons.t b/testcases/t/116-nestedcons.t
index 6a2274d4d..7b15c5f0e 100644
--- a/testcases/t/116-nestedcons.t
+++ b/testcases/t/116-nestedcons.t
@@ -73,6 +73,7 @@ my $expected = {
     workspace_layout => 'default',
     current_border_width => -1,
     marks => $ignore,
+    window_icon_padding => -1,
 };
 
 # a shallow copy is sufficient, since we only ignore values at the root
diff --git a/testcases/t/187-commands-parser.t b/testcases/t/187-commands-parser.t
index 723a7563d..3404df1fb 100644
--- a/testcases/t/187-commands-parser.t
+++ b/testcases/t/187-commands-parser.t
@@ -54,6 +54,7 @@ is(parser_calls(
    'move workspace foobar; ' .
    'move workspace torrent; ' .
    'move workspace to output LVDS1; ' .
+   'move to output LVDS1 DVI1; ' .
    'move workspace 3: foobar; ' .
    'move workspace "3: foobar"; ' .
    'move workspace "3: foobar, baz"; '),
@@ -62,7 +63,11 @@ is(parser_calls(
    "cmd_move_con_to_workspace_name(3, (null))\n" .
    "cmd_move_con_to_workspace_name(foobar, (null))\n" .
    "cmd_move_con_to_workspace_name(torrent, (null))\n" .
-   "cmd_move_workspace_to_output(LVDS1)\n" .
+   "cmd_move_con_to_output(LVDS1, 1)\n" .
+   "cmd_move_con_to_output(NULL, 1)\n" .
+   "cmd_move_con_to_output(LVDS1, 0)\n" .
+   "cmd_move_con_to_output(DVI1, 0)\n" .
+   "cmd_move_con_to_output(NULL, 0)\n" .
    "cmd_move_con_to_workspace_name(3: foobar, (null))\n" .
    "cmd_move_con_to_workspace_name(3: foobar, (null))\n" .
    "cmd_move_con_to_workspace_name(3: foobar, baz, (null))",
@@ -171,6 +176,7 @@ is(parser_calls('unknown_literal'),
        scratchpad
        swap
        title_format
+       title_window_icon
        mode
        bar
        gaps
diff --git a/testcases/t/201-config-parser.t b/testcases/t/201-config-parser.t
index 2d8b63c7a..39eb80cb9 100644
--- a/testcases/t/201-config-parser.t
+++ b/testcases/t/201-config-parser.t
@@ -506,6 +506,7 @@ EOT
 
 my $expected_all_tokens = "ERROR: CONFIG: Expected one of these tokens: <end>, '#', '" . join("', '", 'set ', 'set	', qw(
         set_from_resource
+        include
         bindsym
         bindcode
         bind
diff --git a/testcases/t/254-move-to-output-with-criteria.t b/testcases/t/254-move-to-output-with-criteria.t
index 17aa1bbc8..c129aa715 100644
--- a/testcases/t/254-move-to-output-with-criteria.t
+++ b/testcases/t/254-move-to-output-with-criteria.t
@@ -41,4 +41,12 @@ is_num_children($ws_top_right, 1, 'one container on the upper right workspace');
 is_num_children($ws_bottom_left, 0, 'no containers on the lower left workspace');
 is_num_children($ws_bottom_right, 1, 'one container on the lower right workspace');
 
+# Also test with multiple explicit outputs
+cmd '[class="moveme"] move window to output fake-1 fake-2';
+
+is_num_children($ws_top_left, 0, 'no containers on the upper left workspace');
+is_num_children($ws_top_right, 1, 'one container on the upper right workspace');
+is_num_children($ws_bottom_left, 1, 'one container on the lower left workspace');
+is_num_children($ws_bottom_right, 0, 'no containers on the lower right workspace');
+
 done_testing;
diff --git a/testcases/t/312-regress-layout-default.t b/testcases/t/312-regress-layout-default.t
new file mode 100644
index 000000000..b23cf50b7
--- /dev/null
+++ b/testcases/t/312-regress-layout-default.t
@@ -0,0 +1,25 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • https://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • https://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • https://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • http://onyxneon.com/books/modern_perl/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Verifies i3 does not crash when using layout default.
+# Ticket: #4408
+# Bug still in: 4.19.2-83-gc8158875
+use i3test;
+
+cmd 'layout default';
+fresh_workspace;
+
+done_testing;
diff --git a/testcases/t/313-include.t b/testcases/t/313-include.t
new file mode 100644
index 000000000..9b8b0fabb
--- /dev/null
+++ b/testcases/t/313-include.t
@@ -0,0 +1,361 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • https://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • https://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • https://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • http://onyxneon.com/books/modern_perl/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Verifies the include directive.
+
+use File::Temp qw(tempfile tempdir);
+use File::Basename qw(basename);
+use i3test i3_autostart => 0;
+
+# starts i3 with the given config, opens a window, returns its border style
+sub launch_get_border {
+    my ($config) = @_;
+
+    my $pid = launch_with_config($config);
+
+    my $i3 = i3(get_socket_path(0));
+    my $tmp = fresh_workspace;
+
+    my $window = open_window(name => 'special title');
+
+    my @content = @{get_ws_content($tmp)};
+    cmp_ok(@content, '==', 1, 'one node on this workspace now');
+    my $border = $content[0]->{border};
+
+    exit_gracefully($pid);
+
+    return $border;
+}
+
+#####################################################################
+# test thet windows get the default border
+#####################################################################
+
+my $config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+EOT
+
+is(launch_get_border($config), 'normal', 'normal border');
+
+#####################################################################
+# now use a variable and for_window
+#####################################################################
+
+my ($fh, $filename) = tempfile(UNLINK => 1);
+my $varconfig = <<'EOT';
+set $vartest special title
+for_window [title="$vartest"] border none
+EOT
+print $fh $varconfig;
+$fh->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $filename
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# nested includes
+################################################################################
+
+my ($indirectfh, $indirectfilename) = tempfile(UNLINK => 1);
+print $indirectfh <<EOT;
+include $filename
+EOT
+$indirectfh->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $indirectfilename
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# nested includes with relative paths
+################################################################################
+
+my $relative = basename($filename);
+my ($indirectfh2, $indirectfilename2) = tempfile(UNLINK => 1);
+print $indirectfh2 <<EOT;
+include $relative
+EOT
+$indirectfh2->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $indirectfilename2
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# command substitution
+################################################################################
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include `echo $filename`
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# failing command substitution
+################################################################################
+
+$config = <<'EOT';
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include i3-`false`.conf
+
+set $vartest special title
+for_window [title="$vartest"] border none
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# permission denied
+################################################################################
+
+my ($permissiondeniedfh, $permissiondenied) = tempfile(UNLINK => 1);
+$permissiondeniedfh->flush;
+my $mode = 0055;
+chmod($mode, $permissiondenied);
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $permissiondenied
+include $filename
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# dangling symlink
+################################################################################
+
+my ($danglingfh, $dangling) = tempfile(UNLINK => 1);
+unlink($dangling);
+symlink("/dangling", $dangling);
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $dangling
+set \$vartest special title
+for_window [title="\$vartest"] border none
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# variables defined in the main file and used in the included file
+################################################################################
+
+my ($varfh, $var) = tempfile(UNLINK => 1);
+print $varfh <<'EOT';
+for_window [title="$vartest"] border none
+
+EOT
+$varfh->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+set \$vartest special title
+include $var
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+SKIP: {
+    skip "not implemented";
+
+################################################################################
+# variables defined in the included file and used in the main file
+################################################################################
+
+($varfh, $var) = tempfile(UNLINK => 1);
+print $varfh <<'EOT';
+set $vartest special title
+EOT
+$varfh->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $var
+for_window [title="\$vartest"] border none
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+}
+
+################################################################################
+# workspace names are loaded in the correct order (before reorder_bindings)
+################################################################################
+
+# The included config can be empty, the issue lies with calling parse_file
+# multiple times.
+my ($wsfh, $ws) = tempfile(UNLINK => 1);
+$wsfh->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+bindsym 1 workspace 1: eggs
+bindsym Mod4+Shift+1 workspace 11: tomatoes
+
+include $var
+EOT
+
+# starts i3 with the given config, opens a window, returns its border style
+sub launch_get_workspace_name {
+    my ($config) = @_;
+
+    my $pid = launch_with_config($config);
+
+    my $i3 = i3(get_socket_path(0));
+    my $name = $i3->get_workspaces->recv->[0]->{name};
+
+    exit_gracefully($pid);
+
+    return $name;
+}
+
+is(launch_get_workspace_name($config), '1: eggs', 'workspace name');
+
+################################################################################
+# loop prevention
+################################################################################
+
+my ($loopfh1, $loopname1) = tempfile(UNLINK => 1);
+my ($loopfh2, $loopname2) = tempfile(UNLINK => 1);
+
+print $loopfh1 <<EOT;
+include $loopname2
+EOT
+$loopfh1->flush;
+
+print $loopfh2 <<EOT;
+include $loopname1
+EOT
+$loopfh2->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+# loop
+include $loopname1
+
+set \$vartest special title
+for_window [title="\$vartest"] border none
+EOT
+
+is(launch_get_border($config), 'none', 'no border');
+
+################################################################################
+# Verify the GET_VERSION IPC reply contains all included files
+################################################################################
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+include $indirectfilename2
+EOT
+
+my $pid = launch_with_config($config);
+
+my $i3 = i3(get_socket_path(0));
+my $version = $i3->get_version()->recv;
+my $included = $version->{included_config_file_names};
+
+is_deeply($included, [ $indirectfilename2, $filename ], 'included config file names correct');
+
+exit_gracefully($pid);
+
+################################################################################
+# Verify the GET_CONFIG IPC reply returns the top-level config
+################################################################################
+
+my $tmpdir = tempdir(CLEANUP => 1);
+my $socketpath = $tmpdir . "/config.sock";
+ok(! -e $socketpath, "$socketpath does not exist yet");
+
+my ($indirectfh3, $indirectfilename3) = tempfile(UNLINK => 1);
+my $indirectconfig = <<EOT;
+for_window [title="\$vartest"] border none
+include $relative
+EOT
+print $indirectfh3 $indirectconfig;
+$indirectfh3->flush;
+
+$config = <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+set \$vartest special title
+
+include $indirectfilename3
+
+ipc-socket $socketpath
+EOT
+
+my $pid = launch_with_config($config, dont_add_socket_path => 1, dont_create_temp_dir => 1);
+
+my $i3 = i3(get_socket_path(0));
+my $config_reply = $i3->get_config()->recv;
+
+is($config_reply->{config}, $config, 'GET_CONFIG returns the top-level config file');
+
+my $included = $config_reply->{included_configs};
+is(scalar @{$included}, 3, 'included_configs contains all 3 files');
+is($included->[0]->{raw_contents}, $config, 'included_configs->[0]->{raw_contents} contains top-level config');
+is($included->[1]->{raw_contents}, $indirectconfig, 'included_configs->[1]->{raw_contents} contains indirect config');
+is($included->[2]->{raw_contents}, $varconfig, 'included_configs->[2]->{raw_contents} contains variable config');
+
+my $indirect_replaced_config = <<EOT;
+for_window [title="special title"] border none
+include $relative
+EOT
+is($included->[1]->{variable_replaced_contents}, $indirect_replaced_config, 'included_configs->[1]->{variable_replaced_contents} contains config with variables replaced');
+
+exit_gracefully($pid);
+
+
+done_testing;
diff --git a/testcases/t/314-window-icon-padding.t b/testcases/t/314-window-icon-padding.t
new file mode 100644
index 000000000..5320ab9f8
--- /dev/null
+++ b/testcases/t/314-window-icon-padding.t
@@ -0,0 +1,62 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • https://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • https://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • https://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • http://onyxneon.com/books/modern_perl/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Verifies title_window_icon behavior.
+use i3test i3_autostart => 0;
+
+sub window_icon_padding {
+    my ($ws) = @_;
+    my ($nodes, $focus) = get_ws_content($ws);
+    ok(@{$nodes} == 1, 'precisely one container on workspace');
+    return $nodes->[0]->{'window_icon_padding'};
+}
+
+my $config = <<"EOT";
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+EOT
+my $pid = launch_with_config($config);
+
+my $tmp = fresh_workspace;
+
+cmd 'open';
+is(window_icon_padding($tmp), -1, 'window_icon_padding defaults to -1');
+
+cmd 'title_window_icon on';
+isnt(window_icon_padding($tmp), -1, 'window_icon_padding no longer -1');
+
+exit_gracefully($pid);
+
+################################################################################
+# Verify title_window_icon can be used with for_window as expected
+################################################################################
+
+$config = <<"EOT";
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+for_window [class=".*"] title_window_icon padding 3px
+EOT
+$pid = launch_with_config($config);
+
+$tmp = fresh_workspace;
+
+open_window;
+is(window_icon_padding($tmp), 3, 'window_icon_padding set to 3');
+
+exit_gracefully($pid);
+
+done_testing;
diff --git a/testcases/t/315-all-criterion.t b/testcases/t/315-all-criterion.t
new file mode 100644
index 000000000..f11410fdb
--- /dev/null
+++ b/testcases/t/315-all-criterion.t
@@ -0,0 +1,90 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • https://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • https://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • https://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • http://onyxneon.com/books/modern_perl/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Tests all kinds of matching methods
+#
+use i3test;
+
+my $tmp = fresh_workspace;
+
+ok(@{get_ws_content($tmp)} == 0, 'no containers yet');
+
+# Open a new window
+my $window = open_window;
+my $content = get_ws_content($tmp);
+ok(@{$content} == 1, 'window mapped');
+my $win = $content->[0];
+
+######################################################################
+# check that simple matching works.
+######################################################################
+cmd '[all] kill';
+
+sync_with_i3;
+
+is_num_children($tmp, 0, 'window killed');
+
+######################################################################
+# check that simple matching against multiple windows works.
+######################################################################
+
+$tmp = fresh_workspace;
+
+my $left = open_window;
+ok($left->mapped, 'left window mapped');
+
+my $right = open_window;
+ok($right->mapped, 'right window mapped');
+
+# two windows should be here
+is_num_children($tmp, 2, 'two windows opened');
+
+cmd '[all] kill';
+
+sync_with_i3;
+
+is_num_children($tmp, 0, 'two windows killed');
+
+######################################################################
+# check that multiple criteria work are checked with a logical AND,
+# not a logical OR (that is, matching is not cancelled after the first
+# criterion matches).
+######################################################################
+
+$tmp = fresh_workspace;
+
+my $left = open_window(name => 'left');
+ok($left->mapped, 'left window mapped');
+
+my $right = open_window(name => 'right');
+ok($right->mapped, 'right window mapped');
+
+# two windows should be here
+is_num_children($tmp, 2, 'two windows opened');
+
+cmd '[all title="left"] kill';
+
+sync_with_i3;
+
+is_num_children($tmp, 1, 'one window still there');
+
+cmd '[all] kill';
+
+sync_with_i3;
+
+is_num_children($tmp, 0, 'all windows killed');
+
+done_testing;
diff --git a/testcases/t/543-move-workspace-to-multiple-outputs.t b/testcases/t/543-move-workspace-to-multiple-outputs.t
new file mode 100644
index 000000000..b9bfabec8
--- /dev/null
+++ b/testcases/t/543-move-workspace-to-multiple-outputs.t
@@ -0,0 +1,93 @@
+#!perl
+# vim:ts=4:sw=4:expandtab
+#
+# Please read the following documents before working on tests:
+# • https://build.i3wm.org/docs/testsuite.html
+#   (or docs/testsuite)
+#
+# • https://build.i3wm.org/docs/lib-i3test.html
+#   (alternatively: perldoc ./testcases/lib/i3test.pm)
+#
+# • https://build.i3wm.org/docs/ipc.html
+#   (or docs/ipc)
+#
+# • http://onyxneon.com/books/modern_perl/modern_perl_a4.pdf
+#   (unless you are already familiar with Perl)
+#
+# Test using multiple workspaces for 'move workspace to output …'
+# Ticket: #4337
+use i3test i3_config => <<EOT;
+# i3 config file (v4)
+font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
+
+fake-outputs 1024x768+0+0,1024x768+1024+0,1024x768+0+768,1024x768+1024+768
+EOT
+
+# Test setup: 4 outputs 2 marked windows
+
+open_window;
+cmd 'mark aa, move to workspace 1, workspace 1';
+open_window;
+cmd 'mark ab, move to workspace 3';
+
+sub is_ws {
+    my $ws_num = shift;
+    my $out_num = shift;
+    my $msg = shift;
+
+    local $Test::Builder::Level = $Test::Builder::Level + 1;
+    is(get_output_for_workspace("$ws_num"), "fake-$out_num", "Workspace $ws_num -> $out_num: $msg");
+}
+
+###############################################################################
+# Test using "next" special keyword
+###############################################################################
+
+is_ws(1, 0, 'sanity check');
+is_ws(3, 2, 'sanity check');
+
+for (my $i = 1; $i < 9; $i++) {
+    cmd '[con_mark=a] move workspace to output next';
+    my $out1 = $i % 4;
+    my $out3 = ($i + 2) % 4;
+
+    is_ws(1, $out1, 'move workspace to next');
+    is_ws(3, $out3, 'move workspace to next');
+}
+
+###############################################################################
+# Same as above but explicitely type all the outputs
+###############################################################################
+
+is_ws(1, 0, 'sanity check');
+is_ws(3, 2, 'sanity check');
+
+for (my $i = 1; $i < 10; $i++) {
+    cmd '[con_mark=a] move workspace to output fake-0 fake-1 fake-2 fake-3';
+    my $out1 = $i % 4;
+    my $out3 = ($i + 2) % 4;
+
+    is_ws(1, $out1, 'cycle through explicit outputs');
+    is_ws(3, $out3, 'cycle through explicit outputs');
+}
+
+###############################################################################
+# Use a subset of the outputs plus some non-existing outputs
+###############################################################################
+
+cmd '[con_mark=aa] move workspace to output fake-1';
+cmd '[con_mark=ab] move workspace to output fake-1';
+is_ws(1, 1, 'start from fake-1 which is not included in output list');
+is_ws(3, 1, 'start from fake-1 which is not included in output list');
+
+my @order = (0, 3, 2);
+for (my $i = 0; $i < 10; $i++) {
+    cmd '[con_mark=a] move workspace to output doesnotexist fake-0 alsodoesnotexist fake-3 fake-2';
+
+    my $out = $order[$i % 3];
+    is_ws(1, $out, 'cycle through shuffled outputs');
+    is_ws(3, $out, 'cycle through shuffled outputs');
+
+}
+
+done_testing;
diff --git a/travis/bintray-autobuild-debian.json b/travis/bintray-autobuild-debian.json
deleted file mode 100644
index d01b7dbaa..000000000
--- a/travis/bintray-autobuild-debian.json
+++ /dev/null
@@ -1,36 +0,0 @@
-{
-   "package": {
-        "name": "i3-wm",
-        "repo": "i3-autobuild",
-        "subject": "i3"
-    },
-
-    "version": {
-        "name": "%version%",
-        "desc": "TODO",
-        "gpgSign": false
-    },
-
-    "files": [
-        {
-            "includePattern": "distbuild/deb/debian-amd64/(.*\\.deb)$",
-	    "matrixParams": {
-                "deb_distribution": "sid",
-                "deb_component": "main",
-                "deb_architecture": "amd64"
-	    },
-	    "uploadPattern": "$1"
-        },
-        {
-            "includePattern": "distbuild/deb/debian-i386/(.*\\.deb)$",
-	    "matrixParams": {
-                "deb_distribution": "sid",
-                "deb_component": "main",
-                "deb_architecture": "i386"
-	    },
-	    "uploadPattern": "$1"
-        }
-    ],
-
-    "publish": true
-}
diff --git a/travis/bintray-autobuild-ubuntu.json b/travis/bintray-autobuild-ubuntu.json
deleted file mode 100644
index 4c0d6114c..000000000
--- a/travis/bintray-autobuild-ubuntu.json
+++ /dev/null
@@ -1,36 +0,0 @@
-{
-   "package": {
-        "name": "i3-wm",
-        "repo": "i3-autobuild-ubuntu",
-        "subject": "i3"
-    },
-
-    "version": {
-        "name": "%version%",
-        "desc": "TODO",
-        "gpgSign": false
-    },
-
-    "files": [
-        {
-            "includePattern": "distbuild/deb/ubuntu-amd64/(.*\\.deb)$",
-	    "matrixParams": {
-                "deb_distribution": "bionic",
-                "deb_component": "main",
-                "deb_architecture": "amd64"
-	    },
-	    "uploadPattern": "$1"
-        },
-        {
-            "includePattern": "distbuild/deb/ubuntu-i386/(.*\\.deb)$",
-	    "matrixParams": {
-                "deb_distribution": "bionic",
-                "deb_component": "main",
-                "deb_architecture": "i386"
-	    },
-	    "uploadPattern": "$1"
-        }
-    ],
-
-    "publish": true
-}
diff --git a/travis/check-spelling.pl b/travis/check-spelling.pl
index f2e79b514..6357e78a4 100755
--- a/travis/check-spelling.pl
+++ b/travis/check-spelling.pl
@@ -11,6 +11,7 @@
 use v5.10;
 use autodie;
 use lib 'testcases/lib';
+use lib '/usr/share/lintian/lib';
 use i3test::Util qw(slurp);
 use Lintian::Spelling qw(check_spelling);
 
@@ -21,8 +22,6 @@
 my $profile = Lintian::Profile->new;
 $profile->load('debian', ['/usr/share/lintian']);
 
-Lintian::Data->set_vendor($profile);
-
 my $exitcode = 0;
 
 # Whitelist for spelling errors in manpages, in case the spell checker has
@@ -30,6 +29,7 @@
 my $binary_spelling_exceptions = {
     #'exmaple' => 1, # Example for how to add entries to this whitelist.
     'betwen' => 1, # asan_flags.inc contains this spelling error.
+    'dissassemble' => 1, # https://reviews.llvm.org/D93902
 };
 my @binaries = qw(
     build/i3
@@ -41,7 +41,7 @@
     build/i3bar
 );
 for my $binary (@binaries) {
-    check_spelling(slurp($binary), $binary_spelling_exceptions, sub {
+    check_spelling($profile, slurp($binary), $binary_spelling_exceptions, sub {
         my ($current, $fixed) = @_;
         say STDERR qq|Binary "$binary" contains a spelling error: "$current" should be "$fixed"|;
         $exitcode = 1;
@@ -56,7 +56,7 @@
 for my $name (glob('build/man/*.1')) {
     for my $line (split(/\n/, slurp($name))) {
         next if $line =~ /^\.\\\"/o;
-        check_spelling($line, $manpage_spelling_exceptions, sub {
+        check_spelling($profile, $line, $manpage_spelling_exceptions, sub {
             my ($current, $fixed) = @_;
             say STDERR qq|Manpage "$name" contains a spelling error: "$current" should be "$fixed"|;
             $exitcode = 1;
diff --git a/travis/deploy-github-pages.sh b/travis/deploy-github-pages.sh
index 2d4548208..b5ead0be1 100755
--- a/travis/deploy-github-pages.sh
+++ b/travis/deploy-github-pages.sh
@@ -9,6 +9,10 @@ mkdir build.i3wm.org
 cp -r deb/COPY-DOCS build.i3wm.org/docs
 cd build.i3wm.org
 echo build.i3wm.org > CNAME
+# Disallow search engine indexing for build.i3wm.org: users should find the
+# release version instead, and only developers should use build.i3wm.org.
+echo 'User-Agent: *' > robots.txt
+echo 'Disallow: /' >> robots.txt
 git init
 
 git config user.name "Travis CI"
diff --git a/travis/prep-bintray.sh b/travis/prep-bintray.sh
deleted file mode 100755
index 4ea56dcd4..000000000
--- a/travis/prep-bintray.sh
+++ /dev/null
@@ -1,6 +0,0 @@
-#!/bin/sh
-
-set -e
-set -x
-
-sed -i "s,%version%,$(git describe --tags),g" travis/bintray-autobuild-*.json
diff --git a/travis/push-balto.sh b/travis/push-balto.sh
new file mode 100755
index 000000000..ffa5ee15a
--- /dev/null
+++ b/travis/push-balto.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+set -e
+
+for fn in distbuild/deb/debian-amd64/*.deb distbuild/deb/debian-i386/*.deb
+do
+    echo "pushing $fn to balto"
+    curl \
+	--header "Authorization: Bearer ${BALTO_TOKEN}" \
+	--form "package=@${fn}" \
+	--form distribution=all \
+	https://i3.baltorepo.com/i3/i3-autobuild/upload/
+done
+
+for fn in distbuild/deb/ubuntu-amd64/*.deb distbuild/deb/ubuntu-i386/*.deb
+do
+    echo "pushing $fn to balto"
+    curl \
+	--header "Authorization: Bearer ${BALTO_TOKEN}" \
+	--form "package=@${fn}" \
+	--form distribution=all \
+	https://i3.baltorepo.com/i3/i3-autobuild-ubuntu/upload/
+done
diff --git a/travis/skip-pkg.sh b/travis/skip-pkg.sh
index 4337120b7..0ca1d7494 100755
--- a/travis/skip-pkg.sh
+++ b/travis/skip-pkg.sh
@@ -2,11 +2,11 @@
 # Returns true if Debian/Ubuntu packages should be skipped because this CI run
 # was triggered by a pull request.
 
-# Verify BINTRAY_USER is present (only set on github.com/i3/i3),
+# Verify BALTO_TOKEN is present (only set on github.com/i3/i3),
 # otherwise the CI run was triggered by a pull request.
 # Verify CC=gcc so that we only build packages once for each commit,
 # not twice (with gcc and clang).
-if [ ! -z "$BINTRAY_USER" ] && [ "$CC" = "gcc" ]
+if [ ! -z "$BALTO_TOKEN" ] && [ "$CC" = "gcc" ]
 then
 	exit 1
 fi