Bug 508619

Summary: Brief screen freeze when doing Present Windows while running JetBrains IntelliJ IDEA in XWayland mode
Product: [Plasma] kwin Reporter: Raman Gupta <rocketraman>
Component: effects-present-windowsAssignee: KWin default assignee <kwin-bugs-null>
Status: REPORTED ---    
Severity: normal CC: nate
Priority: NOR Keywords: wayland-only
Version First Reported In: 6.4.3   
Target Milestone: ---   
Platform: Other   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=479250
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Raman Gupta 2025-08-22 21:08:35 UTC 
SUMMARY

I have a performance issue with Present Windows on Wayland. The screen briefly freezes when doing Present Windows (for anywhere from no freeze to 3-4 seconds).

I don't know the underlying cause but it seems to happen when I run JetBrains IntelliJ IDEA in its standard X11 mode. The hanging behavior seems to get worse over time -- after a few hours of active system use, Plasma hangs on Present Windows can exceed more than a second.

After Present Windows is executed, doing another Present Windows immediately is fast. But after only a few minutes of normal system use, it has the same hanging issue again.

When configuring IDEA to use its experimental native Wayland mode, the issue is not reproducible. Therefore, the problem seems isolated to XWayland. The only other XWayland applications I am currently running are xscreensaver and this does not appear to cause any issues.

This is a recent problem. I've been using this combination of software for a long time and have never had an issue until recently.


STEPS TO REPRODUCE
1. Run IntelliJ IDEA for several hours using its default X11 mode
2.  Execute Present Windows

OBSERVED RESULT
A Plasma freeze that can last several seconds.

EXPECTED RESULT
No hang / freeze.


SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.1
Kernel Version: 6.15.9-201.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 24 × 12th Gen Intel® Core™ i9-12900KS
Memory: 128 GiB of RAM (124.8 GiB usable)
Graphics Processor: AMD Radeon RX 6600 XT

ADDITIONAL INFORMATION

A potentially related issue is https://bugs.kde.org/show_bug.cgi?id=479250 -- that issue is focused on the task switcher rather than present windows, but comments there also mention JetBrains products.