Folders for auto upload? I have Camera twice (/storage/emulated/0/DCIM/Camera; once for pictures, the other for videos), OpenCamera (/storage/emulated/0/DCIM/OpenCamera) and Screenshots (/storage/emulated/0/DCIM/Screenshots).

(I only tried OpenCamera briefly, recently, and have since uninstalled it. The issue at hand was present already back when I first got this phone and installed Nextcloud on it, last July.)

I’ve always had auto upload enabled until now, so can’t say whether it’s dependent on that. I could try disabling it next time the issue re-emerges; as dictated by Murphy’s law, I was unable to trigger it just now that I intentionally tried to.

Oh, and I am running Beta (so currently 3.11.0 RC4) of the Nextcloud app. Can’t remember when I enrolled in.