Uncle Fester's Toupee - S1-E31
Other mistake: Bad editing shows up a couple times in this episode. Once when Max goes to ring the doorbell. As he reaches for it, it moves out and in on its own and he moves with it. As he does, its easy to see the film is run back and forth. The second time is when he reacts to the news of Kitty. He flinches, and his toupee slips over his face, then the film is run backwards so it goes back.
Chosen answer: Being that this was filmed in a TV studio, the set would have been specially designed and built to accommodate Cassidy's height. Also, I live in an older house (100 years-old), and all the inner and outer doors are eight feet tall.
raywest ★