Add the possibility converting username to lowercase before creating database user

What I would need is a possibility to convert the guacamole username into lowercase before creating the database user, similar to the token usage ${GUAC_USERNAME:lower} for the connection parameter.

If you set up guacamole with LDAP associating with a database and 2FA authentication and also the postgresql-auto-create-accounts: true is set, then the first time the user logs in( for example with only lowercase) , the database entry is created and also the 2FA token is rolled out. But if the user logs in again for example with uppercase first the login also works but there is created a new user in the database with a new 2FA token for it.
It would be comfortabel for administration and usage if the created name in the database (in association with LDAP) is not case sensitive to prevent double users in database.

Regards Andrea