Hello @jancona and welcome to the forum!
–snapshot-policy only supports Windows and Linux, with certain requirements either way. MacOS not yet, however Any plans to support snapshots on the modern Filesystems (ZFS et. al)? is the feature request…
Because you’ve been looking at other #1400 errors, you might have already read that it might be related to files changing at the time, that snapshot might help but if unavailable, workaround is to not back the file up.
Warning: sqlite-journal errors 1400 would be an example of that, and of how you might be able to see what files give trouble. Hopefully they are ones that you won’t mind deselecting as source, or adding an exclude.