Created attachment 143450 [details] camera footage of the glitch SUMMARY Sometimes (I'm not sure what's causing this), there are visual glitches when there is some movement on screen. It looks like a bunch narrow (1 pixel in height) horizontal stripes. STEPS TO REPRODUCE No known way to reproduce. OBSERVED RESULT See camera footage – this glitch does not show up in videos recorded via SimpleScreenRecorder for me. EXPECTED RESULT No visual glitches like this one. SOFTWARE/OS VERSIONS Operating System: KDE neon 5.23 KDE Plasma Version: 5.23.2 KDE Frameworks Version: 5.86.0 Qt Version: 5.15.3 Kernel Version: 5.11.0-38-generic (64-bit) Graphics Platform: X11 Processors: 8 × Intel® Core™ i5-8250U CPU @ 1.60GHz Memory: 7.7 GiB of RAM Graphics Processor: Mesa Intel® UHD Graphics 620 ADDITIONAL INFORMATION Reporting this as kwin bug, because workaround `kwin --replace` seems to fix it for me. I've observed this for quite some time now, so it is not new to the KDE version 5.23.2, and probably also existed in 5.22.* and 5.21.*.
Since 2021, I have 1. upgraded up to KDE 5.27.5. 2. changed my V-sync settings 3. upgraded my monitor I haven't been able to reproduce the bug, so there's no sense in keeping this bug open.