Plot hole: When Dominique is on TV, she says she got the shoes from Al's store. Then the Amish guy comes out to confirm she broke her leg from the shoe he made. Al says yes. She got the shoes way before Al knew he had no more shoes and before they even hired the Amish guy. How can she break her leg from his shoe if he wasn't hired and making them yet?
Suggested correction: Al was passing the blame.
The correction above is correct.
Continuity mistake: In episode 10 (Joey's Place) the Tanner family move Joey into the garage, redecorating it so the entire place is filled with Joey's furniture, but in this episode it shows the characters in and out of the garage which is completely empty and back the way it was before Joey moved in. Later in the episode Joey's stuff is out of the alcove again.
Factual error: Throughout this series we are treated to a set of the House of Commons. Whilst it's almost accurate in nearly every detail, it misses out one crucial aspect. The set only has 4 rows of seating, the real House of Commons has 5.
Visible crew/equipment: In the the episode "In-console-able" from series 19, in the kitchen when Paul accidentally puts custard and hundreds of thousands on a dinner, he puts the lid on it and when the camera zooms in you can see a cameraman with a camera recording and Barry getting ready for his take.
Factual error: David Jason's character visits the bank to pick up the share certificates left to him by a previous Master. Much to his surprise the bank manager tells him that these shares are now worth £500,000. The bank manager looks at the certificates, then at a screen by his desk before making the calculation very quickly in his head. Given that the certificates are decades old this is impossible. It would take a considerable amount of time to work out the new number of shares that the certificates would entitle the bearer to based on share splits and consolidations over the years. Also, the shares would be denominated in pre-decimal currency so they would have to be revalued based on the conversion rate at the time Britain went decimal. It would be a time consuming and painful task to decide their new value.