Bug 453413

Summary: Wayland window flicker after unlock
Product: [Plasma] kwin Reporter: kde.org
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Severity: normal CC: xaver.hugl
Priority: NOR    
Version: 5.24.4   
Target Milestone: ---   
Platform: Manjaro   
OS: Linux   
Latest Commit: Version Fixed In:
Attachments: qdbus org.kde.KWin /KWin supportInformation > supinfo.txt
short video of flickering windows after unlock
output of xrandr --verbose
content of wayland session log output after unlock

Description kde.org 2022-05-05 11:01:19 UTC
Created attachment 148576 [details]
qdbus org.kde.KWin /KWin supportInformation > supinfo.txt

After unlocking the screenlock, windows flicker. Sometimes only the window decoration flickers, sometimes the whole window flickers. This only happens on wayland. X11 works as expected. This happens almost all the times when the desktok is shown after unlocking. The flickering disappears once I move the mouse into the affected window.

1. Log into the Plasma desktop and open a window, e.g. Konsole.
2. Make sure that the mouse cursor is not inside the window.
3. Press Ctrl-Alt l to lock the screen
4. Enter your password and press enter

Windows flicker

Windows do not flicker and are displayed normal as on X11.

Operating System: Manjaro Linux
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Kernel Version: 5.15.32-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 4 × Intel® Core™ i5-4670 CPU @ 3.40GHz
Memory: 15,3 GiB of RAM
Graphics Processor: Mesa DRI Intel® HD Graphics 4600

Comment 1 kde.org 2022-05-05 11:11:05 UTC
Created attachment 148577 [details]
short video of flickering windows after unlock

I attached a small video made with my mobile phone which shows the flickering of the window after unlocking the screen. It also shows that the flickering stops as soon as I move the mouse cursor inside the window.
Comment 2 kde.org 2022-05-05 11:11:54 UTC
Created attachment 148578 [details]
output of xrandr --verbose

Added the output of xrandr --verbose.
Comment 3 kde.org 2022-05-05 11:21:24 UTC
Created attachment 148579 [details]
content of wayland session log output after unlock

A few lines are written to wayland-session.log after unlocking the screen.
Comment 4 kde.org 2022-05-05 11:27:17 UTC
I have noticed the flickering when I tried switching from X11 to Wayland before but haven't reported it, because there were a lot of issues with Wayland which kept me from using it as my daily default environment. I'm giving this another go as it seems to be more stable now and I want to help iron out the remaining bugs. Please let me know if I can provide any other information to help analyzing and hopefully fixing this issue.
Comment 5 Zamundaaa 2022-05-05 11:39:31 UTC

*** This bug has been marked as a duplicate of bug 447705 ***
Comment 6 kde.org 2022-05-13 11:39:32 UTC
After the update, I can confirm that this is fixed in 5.24.5.