Created attachment 142261 [details]
Ugly Xorg crap (context menu) covering active window
I keep using my PC normally. Then I close any program. Suddenly, kwin goes mad and the window "sticks to" my desktop with slightly lower opacity. It remains on top of other windows too.
STEPS TO REPRODUCE
1. Use PC normally
2. Close any program
3. Sometimes, the closed window "sticks", sometimes it doesn't
See attachment. A "sticky" context menu is covering KRunner. Also happens with other windows (both KDE & non-KDE apps)
The context menu shouldn't "stick" in the first place
Linux/KDE Plasma: 5.14.9-arch2-1
(available in About System)
KDE Plasma Version: 5.22.5
KDE Frameworks Version: 5.86.0
Qt Version: 5.15.2+kde+r237-1
The bug is irregular though, like only 1-2% windows "stick" like that. Also it's not yet reproduced in Wayland. May also be an OpenGL or Xorg bug, but I'm a noob and Xorg source code on freedesktop seems spooky, so can't confirm that.
Well, think it's a KWin bug because `kwin_x11 --replace &` removes the "sticky" window. My compositor settings, if necessary, are as follows:
Scale method: Crisp
Rendering backend: OpenGL 3.1
Latency: Prefer lower latency
Tearing prevention ("vsync"): Only when cheap
Keep window thumbnails: Only for Shown Windows
Both `Enable compositor on startup` and `Allow applications to block compositing` are checked. Since no crash is involved, Dr Konqi doesn't come up to help me report a backtrace.
*** This bug has been marked as a duplicate of bug 439815 ***