Hi claytonk:
Thanks for the info i thought so too but was not sure.
Hi bob:
Thanks for the Tipp! If I saw right the login extra has the functionality to choose groups too. But as your extra it is also just for new users if they fill in the register form. If they want to change it it's not possible. Right?
For me the groups are important because I would like to use the people extra and it just works with groups not with extended fields.
I also found your snippet which allows to list all users which have an extended field or an special value in it. Would be perfect, but I need to sort the result an Filter for more than one field.
Maybe I try to enhance it on my own - even though I am just a designer