I don’t have a use case that triggers it, but it often happens that the leftmost toolbar has the input focus while I’m in note entry mode. So in note entry - and it happens when in non note entry, I’m using the arrow keys and what I noticed is that toolbar wiggle a little bit indicating it’s grabbed the focus. Nothing happens in the music score.
I’ll keep an eye out as to what might be triggering this, but note bene there is a leaky focus handling somewhere. AFAIK that tool bar should never have the focus. I’ve seen this prior to the recent update, and it’s occurring with a single window open, not multi window, and that window is full screen.