Around the middle of the episode, when Morty is doing the montage of using the device, he's seen holding the door open for a lady. The sign says "Open" on one side and "Close" on the other (instead of "Closed").
Rick says "I don't respect time travel. If Ant-Man and the Wasp can do it, I'm not Interested." The problem is, 2 episodes earlier (Rattlestar Ricklactica) Rick and Morty time travel a couple times. However, that was because it was necessary rather than for fun like it would have been in this case.