Wow, a quite big discussion emerged out of my initial post. Thank you everybody for your tips.
I’d like to leave some feedback about the original issue.
First of all - I can confirm the issue is gone on Wayland.
The migration went fine for first of my machines. In fact, I think that I could proceed with other machines as well. I am surprised the Wayland environment actually works fine. No serious issues so far.
There is just one thing that I will need to fix / work around somehow.
I use kdocker a lot in my work. Unfortunately it does not work under Wayland.
I didn’t find any alternative yet. I will need to find some solution later on.
It has been the case for a while now that x11 isn’t getting much love any more, and little development is going in to it now, at least as far as the KDE/Plasma devs are concerned. (Other DEs may vary).
One thing though; could I kindly suggest that you mark the post which best helped you as the Solution? Cheers!
You have been a forum member since 2020 and should already know to mark the post that helped you the most, and not your own (as @BG405 mentioned).
Only mark your own post if yours is the actual solution, and nobody else has pointed you in that direction.
As you have already ridden off into the sunset, I’ve taken the liberty of doing this for you, so that those finding this topic in future will find the solution more easily.
Solution? Cheers!