The default behaviour of the app when on startup its unable to open files in the data directory is to crash with a bunch of error messages, one of which is, I believe,
dataDir.checkPermissions
Suggested recovery is to either grant permission to access the directory (which might not be possible to the user, either because of lack of privileges or because the directory was a removed mounted drive, a virtual one provided by flatpack or something similar),
Or to change back the location to the default one, which is not possible trough the app since it instantly crashes.

Currently the only viable recovery options are either deleting the settings folder and letting it reinitialize, or finding the file storing the location which luckily is plaintext and editing manually.

A minimal fix would be directing users to that file in the error message, and a better one would be prompting for a new data directory in the error message.

Thanks,
Dario