Can you maybe explain in a bit more detail? What would the UI look like? How would it function? Why do you think this would be a good feature?
He means they should add a "join lobby" button in the social menu to make it possible to join the lobby, the certain player is currently in.
Im not sure if this is only meant for lobby or for games too.
However, this could revive the problems we already had when the spactator feature was discussed: overfilling lobbies.
Thats why the spectators were limited to people in party.
If we would allow everyone to join the game/lobby via the friend list, this problem would just return.
Incase this suggestion is meant only for lobbies only, I would reather suggest the idea of bringing back /fl showing the exact lobby a player is in. That way you could just join the certain lobby. A "join lobby" button would in this case create problems with already full lobbies.