Thanks for the clarification.
You are right: in this topic, nobody said that plasma-workspace 6.5.6-2 would solve the issue.
Ben only said that the problem is gone with 6.6.
I mentioned plasma-workspace 6.5.6-2 because I had seen a report in another topic saying that it might fix the issue there, so I decided to test it on my system as well.
In my case, on the stable branch, the problem still persists with:
plasma-desktop 6.5.6-1.1plasma-workspace 6.5.6-2
So for now, I will stay on plasma-desktop 6.5.5-1 and wait until 6.6 reaches the stable branch.
Thanks again for the clarification.