Bug 495099

Summary:	Windows flickering (showing windows below for short periods of time)
Product:	[Plasma] kwin	Reporter:	kde
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal	CC:	kdedev, xaver.hugl
Priority:	NOR	Keywords:	multiscreen
Version First Reported In:	6.2.0
Target Milestone:	---
Platform:	Other
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=489350
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	flickering in system tray

Description kde 2024-10-20 16:34:18 UTC

SUMMARY
Sometimes, after the update to plasma 6.2, windows start to flicker, showing windows below for short periods of time.

Most commonly this occurs while watching a video in a browser and moving a mouse or when opening popups (krunner, tray etc). However it can happen in other circumstances too.

This is only visible on my second monitor, so I believe there might be two explanations:
- Bad handling of a second display
- My second display having higher refresh rate than my main one's (144 Hz vs 60 Hz) - seems more reasonable to me

STEPS TO REPRODUCE
1. Use the system
2. Maybe use popups to catalyze the process

OBSERVED RESULT
See wallpaper or windows below show up for a very short period of time

EXPECTED RESULT
The windows are just shown normally

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: kernel 6.11.3-200.fsync.fc40.x86_64 (64-bit); wayland
KDE Plasma Version: 6.2.0
KDE Frameworks Version: 6.7.0
Qt Version: 6.7.2

ADDITIONAL INFORMATION
I attach a video from my phone (for some reason obs does not capture the behaviour)

Comment 1 kde 2024-10-20 17:56:50 UTC

Created attachment 175061 [details]
flickering in system tray

Comment 2 Zamundaaa 2024-11-14 16:49:39 UTC

Please attach the output of drm_info.

> Bad handling of a second display
If it's also on a different GPU, synchronization issues between two GPUs aren't unheard of.

Also, do you have night light enabled? If so, does disabling it remove the issue?

Comment 3 kde 2024-11-14 18:41:43 UTC

Here is drm_info: https://rentry.co/dinm9wtb

I do have night light enabled, but disabling it does not fix the issue.

As for which gpu is used for which monitor - I am not sure. I believe HDMI (so a second display) is soldered directly to nvidia gpu, but I am not sure about the builtin display of my laptop (though, I gravitate towards it using intel integrated gpu)

Comment 4 Bug Janitor Service 2024-11-29 03:46:32 UTC

🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!

Comment 5 Zamundaaa 2025-02-11 15:40:27 UTC


*** This bug has been marked as a duplicate of bug 480799 ***