I own the expansion, my friend does not. For either of us the "Social" menu displays that we were active 4 days ago (right when the big thargoid update came?), and sending each other friend request does nothing - neither of us get a chance to accept, nothing shows up, not even when I select to play Horizons from the launcher. Since it was announced Live players would be able to switch freely between versions I believe this is a bug.
Frontier, please fix.
Frontier, please fix.