MS4 stalling when used on external monitor

I am running MuseScore 4 on a laptop. As long as I have the application on the laptop screen everything is OK. As soon as I "move" the application to my monitor, I can still do stuff, like adding notes etc., but as soon as I try to save, or save-as, the application totally stalls. Nothing works anymore (just little bleeps). I need to "end task" in the task manager and re-start the program (and losing my work..).
I would think this is a bug.
The monitor I am using is an IIyama 2K.