Just a heads-up for people running Geary development mainline (e.g. built from source) or nightly flatpaks, I’m just about to land https://gitlab.gnome.org/GNOME/geary/-/merge_requests/388 which will update the database version for all accounts you run it against.
This isn’t an undoable operation, so you won’t be go back to running an older version of Geary without either restoring your
geary.db files for each account from a backup or deleting then and downloading your mail again. Apologies for the inconvenience, but this was necessary to implement an important feature.