DeletedUser54 Hey! I don't really know if it's connected to hardware.
On my phone I also have some weird UI bugs (for example some weird display behaviour when tapping). I can't return pixel so I'm worrying much, but
I opened issue on GitHub (https://github.com/GrapheneOS/os-issue-tracker/issues/3980) 2 monthes ago.. I didn't receive any information about the issue though.. very sad.. it annoys me too much.
As I see there are many people in GOS Discord experiencing same issue.
On 3rd party launchers I havent experienced it.
So I don't think they will look into it.
I guess it's not connected to hardware because too many people experience white flashes with apps like Discord, Default messages app etc.
I didn't find any useful info in the internet either. Don't really know if it occurs on stock too, don't want reinstalling GOS, but I don't think it does, because we would have seen more reports.
So if you know something would be glad to hear.. but I dont think you do.. sad.