you won't make yourself a name if you follow the rules

I don't suppose anyone has any idea why one particular Scrivener project of mine—not other projects, and not other programs—has got it in its head that it will be maximized or minimized, nothing in between. Or why my attempting to return the project to occupying about 2/5 my screen will result in it refusing to be maximized until I close and reopen the whole program.

ETA: solved!