When I change the filament type while in the send dialogue box a grey window that covers part of the dialogue box remains and persists even when I move to another app. The only way to get rid of it is to quit Bambu Studio.
What version are you using? I’m guessing the Beta version?
I have the same issue Mac version 2.8.2.61. It is making Studio mostly unusable!
Mac beta versions 2.8.2.571 and 2.8.2.61 were both supposed to have fixed this issue. If it persists, it should be reported again on GitHub.