Window not reaching the top of screen - very strange behaviour when resizing
My iMac recently died (I was on Monterey) - and the Apple senior technician recommended I stay on Catalina for now.
I have had to install all the CC software from scratch.
I immediately noticed that the window in ID does not reach the top of the screen like it did before. No matter what I do there is always this annoying gap at the top (see screenshot).
This is driving me crazy, what's going on here?
Also when I try and resize the window, the resizing sometimes acts erratically and shrinks from all directions.
More odd behaviour:
1. The up/down arrows icon used to resize the window from the bottom right does not stay on bottom right corner. It sometimes changes to an arrow icon with a small square underneath, and jumps inwards.
2. When I resize to make smaller, the window jumps outwards and becomes larger (!)
3. When I resize to make larger, the window jumps outwards and goes off the bottom edge of the screen.
4. Window enlarges for no reason when I am using Chrome, and the window is open in the background.
All in all this is terribly erratic behaviour. I never had a single problem in many years of using CS3. CC has been nothing but glitchy and strange behaviour for me. Not impressed or happy with this.
Are there any ways to fix this behaviour? Any help would be much appreciated, thank you.

