Window resize

Big Sur is a major rewrite of Mac's desktop OS. Consequently, that affects every application you use, include Adobe's Creative Suite. Each has to be retooled for the new OS and that takes several months for each software manufacturer to accomplish.

(I've often heard from engineers at major software companies that, although Apple does give them access to the new OS in advance of its launch, it's a very skimpy window they're given, maybe a month or 2. And they say Apple is often adjusting the OS right up to launch, which affects their retooling work. So don't expect any of our software companies' programs to work well enough on a new OS, both Windows and Apple, for at least 3-6 months after its release. Big Sur has been out for only a month.)

At this time, I think most CS apps are running under Big Sur's emulator for older software, so there will likely be many glitches in what we experience.

Might be best to log these problems at www.InDesign.UserVoice.com so that the engineers can be aware of them.

I don't have an answer, just an agreement. I'm experiencing the same issue. The exact thing occurs when I wish to open a new or older document. Window size is essentially a "stamp" size and must be expanded manually. I'm following this thread, hoping we both get an answer soon.