[amsilex]

Hello, everyone
I've been a Kodi user for years, mostly watching live satellite TV.
Ok, long story short, in Ubuntu 24, when in full-screen mode I have horizontal artefacts when scene change quickly, especially when camera move horizontally. I do not have this issue in windowed mode. Interestingly, I do not have this issue in Xfce session, only in Gnome. Also, in standalone mode - Kodi session, this issue persists. 
Gnome is used under Xorg - Wayland is disabled.

Appreciate any suggestion

[DaVu]

To receive meaningful assistance you will need to provide a full debug log.

The instructions are here... debug log (wiki)

If you are using the Basic Method, then ensure the following is applied...
1.Enable debugging in Settings>System Settings>Logging,
2.Restart Kodi
3.Replicate the problem.
4.Upload the log to Kodi Paste Site manually or use the Kodi Logfile Uploader. (wiki) With either method post the link to the log back here.

If you are using the Advanced Method ensure you have correctly created and applied the advancedsettings.xml file (wiki)

In both instances, you should see the word DEBUG throughout the log.

Note: Full logs only. No partial or redacted logs
Do NOT post your logs directly into the forum. Use the Kodi Paste Site. Post the link to your pasted log in the forum

[amsilex]

Thank you for this answer.
Here is my log

Video artefacts was visible while playing local file. However, not sure if it is reflected in anyway in the log.

[Neo1973]

A difference between Xfce and Gnome could be direct scan-out for fullscreen applications. I don't think Xfce supports it. And running Kodi standalone on GBM has some similarities to direct scan-out.

To narrow the problem down, does it occur with hardware accelerated video decoding enabled, disabled or in both cases?

[amsilex]

Stranger thinks have happened..
Of course, HW acceleration is on, in my case VAAPI. After turning it off and on again, the issue has disappeared. However, with this test, I've installed alternative DE, like Plasma, lubuntu, lxqt and didn't notice video distortion in any of them either.

Not being familiar with nitty-gritty of windows manager, compositor and Wayland, I only could suspect, that about 10% of the upper half screen has 'notification window', fully transparent, but always atop. When a scene rapidly changes, it just can't keep up with redrawing, so, there was this issue. 

No Kodi neither add-ons were updated or recompiled this whole time.