Allow pilots in fleet to receive invitations from another fleets so decide whether to join or not.
Also jumping to another fleet right from current fleet without necessety to leave.
In order to make interface more usable (and less exploitable) - to create special tab (or frame) in fleet panel for work with invitations (where invitations are shown). So invitations are no pop-up window design, just a text (or rss message), and have no expiry.
Thanks everyone for reading.