When Frank falls out the window, his cock ring is visible on the ground.
This episode is a callback to Season 2 Episode 3, Dennis and Dee Go on Welfare (2006). The caseworker at the welfare office is the same actress from the earlier episode, and the heavyset man sitting in the chair is also the same actor from that episode.
This episode opens with Mac, Dennis, and Dee arguing over who had the idea to put "the contaminated chickens in the truck"; this is a continuation of the argument they began in S10E04 Charlie Work (2015), where they execute the idea, argue about whose idea it was, and plan to go through an "arbitration process" to settle it.
Charlie mentions his being surrounded by cats throughout the series. When Frank falls out the window, cats can be seen coming in and out of the scene.
In this episode, Dee's ringtone is "Just a Friend"' by Biz Markie, which is the song that Dennis and Dee sing in S02E03 Dennis and Dee Go on Welfare (2006) while out drinking on their stoop.