Allow per-account number of digits
I don't think it's safe to assume that each provider uses the same number of digits for all accounts. For example, the TOTP codes for my Microsoft account use 8 digits, but I'm sure there are people out there who have 6-digit codes instead. It seems like each provider currently has a hard-coded number of digits in the SQLite database, and users cannot change this either from the UI.
It would be useful if users could override the default number of digits for each provider on a per-account basis from the UI.