I´m not sure if this is now the correct category, but I had to choose one.
In my nextcloud the user only can login with username
When I try to login via firstname.lastname@example.org I get the message “Wrong username or password”
(Maybe for explanation - on this server are more services and the other requires email@example.com)
However - is it possible to add an alias to existing User?
username == firstname.lastname@example.org