We are now reusing the user edit dialog for user preferences (link on the user name on top-right in adminCentral), with all the fields that are usually needed to create/edit an user by the security manager.
Anyway, this kind of dialog is intended for changing things like email or password, and the role selection is IMHO something totally unwanted. Keep in mind that this form will be used also by editors that usually neither know what those roles are. Clicking by error on the "remove" button near role or group selections can also lock down the user (ok, it's an user fault, but keep in mind the kind of users this dialog is intended for, as said they don't ever need to know anything about magnolia security).

Said so, the attached patch just adds a specific user-preference dialog that is used only from the link in adminCentral. Same as the "user edit" one but without any role/group selector.
I would like to commit it before 4.0 rc4, I am attaching a patch for now in order to get feedback from devs