Options - Users
The optional settings for the "User" module can be found via the main menu "Extras / Options / User" option.
Enable expert options
Here you can activate the expert options. Field lengths can be changed in the Schema manager with this setting.
Database-dependent case-sensitivity when filtering
With this setting enabled, the database specifies the case sensitivity. With this setting not enabled, the filters work independently of case sensitivity, i.e. entering "a" will return hits containing a lowercase "a" as well as hits with an uppercase "A".