Bug 460335

Summary: Block compositing window rule affects windows on Wayland session
Product: [Plasma] kwin Reporter: nf.pereira
Component: rulesAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: isma.af, nate, xaver.hugl
Priority: NOR Keywords: wayland-only
Version First Reported In: 5.25.5   
Target Milestone: ---   
Platform: Manjaro   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description nf.pereira 2022-10-13 02:20:17 UTC 
SUMMARY

When a Block compositing window rule affects a window, I'm not expecting for there to be any effect on a Plasma Wayland session, as it's not possible to block compositing on Wayland. But I have found an instance where strange behavior happens on RetroArch.

Having a rule of Block compositing set to "Force" for RetroArch makes it exit fullscreen when loading some cores, when it shouldn't be doing so. Removing the rule returns RetroArch to it's normal behavior.

Note that this rule works as expected when running a Plasma X11 session.

STEPS TO REPRODUCE
1. Open a Plasma Wayland session.
2. Set a rule of Block compositing forced to "Yes" to affect the RetroArch window.
3. Open RetroArch and set it to fullscreen.
2. Open a game on the Mesen core.
3. Observe RetroArch exiting fullscreen.

OBSERVED RESULT
RetroArch exists fullscreen if the rule is present to force Block compositing.

EXPECTED RESULT
Block compositing should have zero effects on a Plasma Wayland session.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Manjaro KDE
KDE Plasma Version: 5.25.5
KDE Frameworks Version: 5.98.0
Qt Version: 5.15.6
Comment 1 Bug Janitor Service 2022-10-13 02:33:46 UTC 
Thank you for the bug report!

Please note that Plasma 5.25.5 is not supported for much longer by KDE; supported versions are 5.24, and 5.26 or newer.

If at all possible please upgrade to a supported version and verify that the bug is still happening there.
Comment 2 Zamundaaa 2025-03-17 23:28:24 UTC 
The relevant code in X11Window was all deleted recently, so it can't make a difference anymore.