There was a change in the UI to fix certain corner cases but which also removed this capability.
I used t o do this a lot as “partial cloning”, sharing only the top left portion of my laptop screen with the projector.
I’ve created a ticket to track this but I see it has been closed now.
We will need to create a new one for re-adding this feature but at least the old ticket contains some hints on how to work around this limitation for now.
This is mostly an intentional KDE Plasma Wayland limitation rather than a hardware issue. Older Plasma versions allowed overlapping displays more freely, but the behavior was restricted because it caused various compositor and window-management edge cases under Wayland.
Your setup likely worked before because Plasma previously tolerated these “partial overlap” layouts, especially for projector-style workflows. Later KWin/KScreen changes tightened those rules to avoid rendering, scaling, and fullscreen inconsistencies.
So this is most likely coming from Plasma Wayland’s current display-management behavior, not from your Intel Arc GPU, Lenovo hardware, or Fedora itself.