Halloween - The Final Chapter - S8-E5
Continuity mistake: Roseanne becomes pregnant at the beginning of Season 7, and it is before the Halloween and Thanksgiving episodes, so she is in her first trimester during the holidays. However, Roseanne does not give birth until the following year in the Season 8 Halloween episode. Her pregnancy has lasted for well over a year.
Construction Junction - S8-E16
Continuity mistake: Stumbling in the dark bedroom, Dan rips off one of the bedposts, and he is holding it, while Roseanne turns on the light. Then, in the next shot, suddenly it's back on the bed again. (00:07:30)
Continuity mistake: When a depressed Roseanne emerges from her bedroom after Dan has left her, she tells Nancy and Leon that she wants to turn over her and Jackie's shares of the restaurant to them. She says she wants Nancy and Leon to experience the same sense of accomplishment that she and Jackie felt when they first opened the business. However, Roseanne seems to have forgotten that it was Nancy, along with her, Jackie, and Bev, who started the restaurant.
Continuity mistake: In the episode Terms of Estrangement Part 1, Roseanne goes for an interview at "The old Wellman Factory" which was closed down and turning into a printing press. Then, in the episode Lanford's Elite, Roseanne and Jackie team up with Edgar Wellman Jr. to try to save the factory from shutting down by paying off past due debts and making all the current employees part owners.
Continuity mistake: Harris was born in 1997 (in season 9) so in 2018, that makes her 21 years old, but in the 2018 revival and its spinoff "The Conners", she is depicted as 17-18 years old and attending high school.
