The FAQ says to use the Edit Room menu, but I didn't see any such menu.
In other chat systems, INVITE USER was a big, obvious, and frequently-used button.
Am I blind?
EDIT: new feature requested here
Yeah, the FAQ is lying. I don't know how that sentence slipped in there, but that's not true nor ever was. I'll update it.
You have two ways to invite a user. Either through the little user popup in the life chat:
or on the user's profile page:
Both lists will show you all rooms you can invite the user to, which are rooms that satisfy the following conditions: