Rhaenyra and Alicent trying to straighten out their yuribait feelings that lead absolutely nowhere. Kinda like how Robb and Joffrey had that passionate one night stand when Joffrey stay at Winterfell in the beginning of GoT... wait that never happened...
it was a reference to the scene where Robb sneaks into King's Landing to have a chat with Joffrey, and beg him not to execute Ned