When Larry is logging into his laptop for the video call with the Iranian consul, a folder on his laptop named "Notes for New Show: Curb Your Enthusiasm" can be seen.
Larry complains to the hotel about the tight sheets on his bed. This was also a complaint made by George (Larry's alter ego) in The Trip: Part 1 (1992).
Chappie Johnson, the name that Larry gave Leon was in fact a real baseball player who played in the Negro League from 1895-1920. His real name was George "Chappie" Johnson Jr.