Bug 489665 - KWin (x11) hangs when ALT - TAB pressed after suspend/resume
Summary: KWin (x11) hangs when ALT - TAB pressed after suspend/resume
Status: REPORTED
Alias: None
Product: kwin
Classification: Plasma
Component: tabbox (other bugs)
Version First Reported In: 6.1.1
Platform: Arch Linux Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords: X11-only
Depends on:
Blocks:
 
Reported: 2024-07-03 09:09 UTC by LyCC
Modified: 2025-02-24 17:58 UTC (History)
1 user (show)

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Latest Commit:
Version Fixed/Implemented In:
Sentry Crash Report:

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Description LyCC 2024-07-03 09:09:00 UTC 
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SUMMARY

KWin (x11) hangs when ALT - TAB pressed after suspend/resume. kwin process goes 100% CPU, GUI goes unresponsive, when the process is killed, GUI works again until next alt-tab. Works perfectly fine on first boot, until sleep/resume.


STEPS TO REPRODUCE
1.  sleep computer with multiple windows opened
2.  resume
3.  press alt-tab when multiple windows are opened

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 6.1.1
KDE Frameworks Version: 6.3.0
Qt Version:  6.7.2
Comment 1 LyCC 2024-07-14 17:05:42 UTC 
Disabling "compact/thumbnail/etc" combo fixes the issue. 

Quick windows switching where the preview bar does not appears is working, however, pressing longer ALT-TAB hangs the 
/usr/bin/kwin_x11 --replace 
process with 100 CPU usage and the entire GUI becomes unresponsive until this process is killed.
Comment 2 TraceyC 2025-02-24 17:58:34 UTC 
Adding the x11-only keyword