I was used to develop in the past (probably last year) running a docker Neon image into a Xephyr window. Now I can't do this anymore as nothing is displayed in Xephyr except the mouse pointer. STEPS TO REPRODUCE Simply run the two commands reported here: https://github.com/KDE/docker-neon. 1. Xephyr -screen 1024x768 :1 & 2. docker run -v /tmp/.X11-unix:/tmp/.X11-unix kdeneon/plasma:unstable OBSERVED RESULT Xephyr only shows black with the mouse pointer inside (which is different from the one of the host). EXPECTED RESULT I should see the Plasma desktop. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Kubuntu 19.04 KDE Plasma Version: 5.16.1 KDE Frameworks Version: 5.59.0 Qt Version: 5.12.2 ADDITIONAL INFORMATION I attached logs docker is printing to stdour/stderr. I see many errors, so it is difficult to understand for me which are relevant.
Created attachment 121219 [details] Logs from the docker image.
This seems to be a problem that appeared in KWin in the last 6 months or so. The desktop runs fine but as soon as your run KWin the window contents are just black. There are window borders which show.