Screen Notifications might cause Graphic-Corruption

• Retroarch Verison 1.14.0 Hotfix 1 (Steam) but also happend in previous (non steeam) versions,
• Windows 10
• Only seems to happen on AMD, reproduced it on two different GPUS (RX570/RX6600), couldn't reproduce it on aother System with a GTX970
• Not sure if related to the driver.. i have tested the latest AMD driver where it still would appear "sometimes". However the "best" driver to reproduce it seems to be 22.10.3.

So to test this with the "recommended" driver. All you have to do is starting retroarch (bordleess fullscreen / 1080p in case that matters), then launching the game F-Zero X (Japan) with the Mupen Plus Next Core. Right at the "first" Screen of the Game you'll then notice some odd "Border" around the screen (on the screenshot it seems like it's just on one corner, but usually it will be a border around the whole game screen). Which will flicker. If you can't reproduce it straight away, you might set up some game remap and cheevos and restart retroach so that you would get the "remap loaded popup" when starting the game. I have had it happen without it but it might help to "force" it to happen.

If you let it stay on the "Flicker-Border-Screen" for a while the game runs a Gameplay Demo and the "Border" will be gone. If you take a screenshot within retroarch (F8) or Steam (F12) you won't see it on the Screenshot. BUT if you take the screenshot with the windows screenshot tool instead you'll be able to catch it (My Screenshot will look different from yours since i'm using the 64DD but it doesn't matter, it happens on the "normal" Game as well).

So after "accepting" that issue for a while i tried to investigate what's the cause of it. And i finally seem to have found it.
As soon as i disable "Screen Notifications" and then start the Game the Issue won't show up.
It's not game breaking and i didn't see it on any other game so far. But i wanted to report this investigation since i have tested and reproduced it on two different Computers (with different AMD GPUs) and the Issue seems to be caused by the "Screen Notifications".
Maybe this investigation will be helpful in any way :)

Reproduce the flickering border in RetroArch on Windows with screen notifications enabled, using F-Zero X (Japan) and the Mupen Plus Next core at startup. Compare the result after disabling Screen Notifications, and trace the screen-notification rendering path to identify why the corruption appears; done means the notification can remain enabled without the border or flicker.