Mouse pointer randomly leaves artifacts on screen


since I upgraded to Fedora 32, I have often noticed that the mouse pointer leaves traces. Essentially, what remains as a trace is a single, partially incomplete, copy of the mouse pointer. So far, I have not been able to determine if this is related to a specific application or mouse gesture.

To me it looks as if the screen is simply not redrawn properly. Sometimes it happens multiple times within some minutes, sometimes everything is fine for hours. The issue is only present in GNOME Wayland, the X session runs without problems.

Does anyone have an idea where to start debugging? Here is some system information:

does your thinkpad have a touchpad? And is it ON or OFF when you use a mouse?

Yes, it has a touchpad and it is enabled. I do not use an external mouse, if your question implies that. Just the touchpad and the track point.

In gnome tweak tool you could try different settings for touchpad. disable touchpad while typing usw.

Well, I do not think that it is a touchpad issue, as it works with X. Both, Wayland and X, should use libinput as the touchpad driver.

My impression is that it might be related to the GPU driver (amdgpu) or the compositor. The driver has seen a lot of changes for 5.6 (see here). Maybe I should try running one of the 5.7 RCs.

So, I did some research. The problem is related to these bugs in Mutter.

$ journalctl -e /usr/bin/gnome-shell
[...] Failed to set hardware cursor (drmModeSetCursor failed: Invalid argument), using OpenGL from now on