When I use FUSE and when I use a notebook, which is stored in the virtual drive (vault), OneNote after a certain time is closed for no reason.
When I use Dokany 1.5.1 or WebDAV, it doesn’t happen.
What to do to fix it for FUSE?
I’m afraid you cannot fix it on your side. There exists already a ticket on our issue tracker, see Problem with FUSE and OneNote. · Issue #2288 · cryptomator/cryptomator · GitHub and we confirmed the bug.