Bug 487598

Summary:	Firefox window on X11 - flickers, shows graphics from previously closed window
Product:	[Plasma] kwin	Reporter:	Daniel Cleaver <daninshed>
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	REPORTED ---
Severity:	normal	CC:	kdedev
Priority:	NOR	Keywords:	multiscreen, X11-only
Version First Reported In:	6.0.4
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	Flickering with 404 page Flickering with taskbar switcher

Description Daniel Cleaver 2024-05-26 17:24:29 UTC

SUMMARY
When using Firefox, I occasionally see a flickering effect on all or part of the window. It typically happens while I move or interact with something else on my second monitor. I can't reproduce this on command, but it happens often enough that I was able to get some videos of it, which I will try to attach. Recently, the flickering area contains a white "404" page. This is from a firefox window that I closed hours or days ago, not one that is currently open.

STEPS TO REPRODUCE
1. Open firefox on right monitor
2. Maximize another program on left monitor
3. Restore and drag program around on left monitor

1. Open firefox on right monitor
2. Hover over the firefox taskbar icon on left monitor, showing previews of all open windows
3. Hover over different preview windows

OBSERVED RESULT
- Flickering areas
- Graphics are displayed that are from a previously closed firefox window

EXPECTED RESULT
Normal behavior when viewing and moving windows.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.0.4
KDE Frameworks Version: 6.2.0
Qt Version: 6.7.0
Kernel Version: 6.9.1-arch1-1

ADDITIONAL INFORMATION
Graphics Platform: X11
Graphics Processor: AMD Radeon RX 6700 XT
Right monitor: Gigabyte M27Q 2560x1440
Left monitor: Asus VG248QE 1920x1080

Comment 1 Daniel Cleaver 2024-05-26 17:28:03 UTC

Created attachment 169857 [details]
Flickering with 404 page

Comment 2 Daniel Cleaver 2024-05-26 17:48:20 UTC

Created attachment 169858 [details]
Flickering with taskbar switcher

Comment 3 Daniel Cleaver 2024-05-26 19:03:15 UTC

Actually, I got the issue to happen on either monitor.

Comment 4 Daniel Cleaver 2024-06-22 22:51:32 UTC

The flickering issue is also present with the following configuration:
KDE Plasma 5.27.10
KDE Frameworks 5.115.0
QT 5.15.12
Kernel: 6.6.20-1-lts

Comment 5 TraceyC 2025-02-10 22:10:23 UTC

This looks like the same effect as bug 495099 except that's for Wayland, this is X11
Both have two monitors involved

Comment 6 TraceyC 2025-02-24 17:59:05 UTC

Adding the x11-only keyword