Bug: 'FMP' does not grey-out sends pan knobs when you re-open a session.
 

This bug has no affect on your audio, but if you set a send to 'Follow-Main-Pan', you'll notice that the Pan fader becomes greyed out (as it should).

However if you re-open the session, the pan faders are not greyed out. You can interact with the send and they will grey out again, but it's just a bit annoying having to double check which sends are FMP and which aren't when opening a session.