Feature request: Confirm mounting of remote locations or automount

I've been setting up to backup to a remote location rather than keep timeshift data locally. The main headache is if that remote location isn't available for some reason, in which case the timeshift data winds up dumping to the empty mount folder, using up space on the local drive for no good reason.

Ideally, timeshift really needs to integrate remote access just like gui file shares, being able to save to something like: smb://user?passwd@my.nas.lan/backup/this_machine and have timeshift automount to a temporary folder and unmount when it's done, sending a notification if something fails. This wouldn't be trivial, unfortunately.

You could workaround by placing a marker file in the empty mount folder telling timeshift to halt and notify there was an error if this file was found. The file would be hidden by the remote location whenever it was properly mounted. This would be a bit annoying to put in place and would require more knowledge of how mounting remote locations works.

The issue names no files, tests, or entry points. Start by mapping how Timeshift selects and verifies snapshot locations, then investigate the proposed remote automount and empty-mount-folder marker alternatives. Done would require an agreed approach for unavailable remote locations, safe mounting behavior, and failure notification.