Other mistake: When the opening credits are shown, the door to the basement is in the kitchen. In the beginning of the series the door is still in the kitchen, but in later seasons the basement door is in the laundry room, but in the opening credits it is still in the kitchen.
Suggested correction: I had noticed the same thing and thought it was a continuity mistake. However, in Season 3, Dan mentioned building the back service porch where Roseanne does the laundry. There are two basement accesses, the one in the kitchen, and what was probably the outside entrance in the backyard that is now enclosed inside the service porch. The family prefers using that one. Most houses, mine own included, have multiple basement access, one inside the house and one outside. In my state, it's a building code requirement.
The Last Thursday in November - S8-E8
Other mistake: Roseanne gave birth to Jerry on October 31st. That Thanksgiving, on November 21st, Jerry was only 3 weeks old. However, he is side by side with Andy sitting in a high chair on his own, sitting straight up, holding his own head up.
Other mistake: The episode where Dan's dad visits and says he invented the rear windshield wiper he says Dan was 3 years old and Audrey was 8 months pregnant, but Dan's an only child.
Other mistake: After the crazy guy threatened Roseanne when she was working alone at the Lunch Box, Dan wanted to teach her and Jackie how to use a gun for protection. Dan seems to have forgotten that Jackie was a cop for the Lanford Police Force and already is trained in firearms use. He regularly saw her in uniform with a sidearm.
