Help with Building Krita with Docker on Linux

Develop Developer Questions
1

Hi, I’m following this guide:

I’m using wsl on windows 11.

when I run this ../krita.appdir/usr/bin/krita after all installation is done I get these errors:

QStandardPaths: wrong permissions on runtime directory /tmp/xdg-runtime/, 0755 instead of 0700
qt.qpa.xcb: could not connect to display :0
qt.qpa.plugin: Could not load the Qt platform plugin “xcb” in “” even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

I’ve tried reinstalling but got the same problem. I’ve also run glxgears on the host system but it didn’t help. I’d love some help with how can I run it successfully, thanks!

p.s - I’m not really sure if I’m supposed to develop on a Qt6 version of krita, or on the earlier version. What’s the difference between them?

2

Have you tried changing the permissions for that file to what’s specified in the error message?

3

could you try running glxgears inside the container? if that doesn’t work it probably means that on container creation it didn’t properly detect x11, and didn’t pass it through properly.

To fix that, you need to comment out the x11 detection if statement and re run the container

diff --git a/bin/run_container b/bin/run_container
index 2ea7d3d..c84597c 100755
--- a/bin/run_container
+++ b/bin/run_container
@@ -80,12 +80,11 @@ if [[ -n ${INTERNAL_PULSEAUDIO_SOCKET} ]]; then
         --volume /tmp/pulseaudio.client.conf:/etc/pulse/client.conf"
 fi
 
-X11_OPTS=
-if [[ -n $XAUTHORITY ]]; then
+# if [[ -n $XAUTHORITY ]]; then
     X11_OPTS="-v /tmp/.X11-unix/:/tmp/.X11-unix
         -v /tmp/krita-docker-xauth:/tmp/krita-docker-xauth:ro
         -e XAUTHORITY=/tmp/krita-docker-xauth"
-fi
+# fi
 
 ${DOCKER_BINARY} run -P -t -d \
   $EXTRA_DOCKER_MOUNTS \

Alternatively you can just run krita with wayland QT_QPA_PLATFORM=wayland krita, which may also fix the issue.

4

As for QT6 vs QT5, the qt6 version has more bugs and issues, especially on wayland. Unless you specifically want to help fixing those bugs it doesn’t matter which version you use. Tho due to some changes between the 2, having both versions of krita is better so that you can test if your changes broke the other version, but that can also be tested in CI, so it’s not a big deal to not have both.

5

I couldn’t open glxgears inside the container, but commenting as you suggested made it work!

Thanks so much :slight_smile: