Dear Maintainer,

I have some issues in the form of graphical artifacts in some applications:
        Discord occasionally shows artifacts (see screenshot #1), when
switching to it from another window. This goes away after interacting with the
application for some time, or switching windows back and forth.

        Chromium displays some SVGs with a blur effect incorrectly(see
screenshot #2). I discovered this while testing my own browser game that uses
SVGs made in Inkscape with a blur effect.

        While the two issues mentioned above are quite insignificant, the game
Planetary Annhilation: Titans is made unplayable. It shows a large, persistent
artifact in the upper half of the screen (see screenshot #3) and opening a UI
menu creates more artifacts that go away when hovering over the menu items.
These issues do not affect the start screen. Starting the game with steam,
steam with disabled steam runtime or from the command line do not make a
difference. Starting the game with the option --software-ui makes the start
screen black, which also makes the game unplayable.
It might be worth noting that the game's UI is made with Coherent UI, which
uses HTML, CSS and JS, so I suspect the issue is only apparent in some web
rendering applications, as Firefox is not affected.

Thank you for your time.

On the left of the Chromium screenshot you see the cursor rendered by
Firefox, on the right is the corrupted version seen in Chromium.

Can you confirm this issue is/is-not relevant any more on either of:-
* Debian Bullseye (testing)
* Debian Buster (stable) with the backported version of kernel
    (5.10.0-0.bpo.7)  installed.

Amdgpu has improved a long way since the time this bug report was
created, and would be good to get the bug closed or issue forwarded
upstream if still relevant.