The questline of "Behind the Looking Glass (Alice)".
If you went to the nightclub and got past the bouncer before meeting Alice, her questline in the 'book' from the ↙ corner stops at "Visit the club - Travel downtown on Friday" and will not progress anymore, even after you triggered sex scenes with her (either route) or even found her at home on Halloween.
This bug does not stop you from befriending her or prevent any cutscenes from happening; it just leaves an unfinished quest in your log, and you may never be able to play the DnD game with her at Tasha's. This may be because she is not considered 'unlocked' properly in the quest system, but whatever.