The problem:
On some hardware, Brave shows regularly rectangular pieces of the desktop through its window as if it doesn't know which part should be in front of the other.
The "pavlovian" logical step which doesn't work (not on its own):
Switching off hardware acceleration
The solution:
Switch off "Memory Saver" in preferences, see below
EDIT: you might have to disable Memory Saver AND hardware acceleration on some hardware
