SUMMARY

I just resumed my KDE - Wayland desktop back from sleep.
I am familiar with the usual one screen stays black while the other one works thing and sometimes no monitor comes back at all.
But this time I experienced a new sort of bug: I was able to log in, both screens were active.
However, on the primary screen, a part of the background stayed black and the was extremely flickering when I moved my mouse cursor.
I managed to capture a video with my phone - I should definitely say  there is an epilepsy warning!
You can find the video here (too large for the uploads): https://youtu.be/iaTxlWAocZ8

STEPS TO REPRODUCE
1. Resume the pc from sleep
2. Log into Plasma 
3. 

OBSERVED RESULT
A part of the screen was flickering very hard.

EXPECTED RESULT
The background should not start to flicker.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Manjaro Linux
(available in About System)
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3

ADDITIONAL INFORMATION
I don't know which logs would be relevant in this case, but if you tell me what you need, I will add it to this issue if this happens again.