Continuity mistake: When Marge and Ruth and shooting cans, there are five on the fence, then, in the next shot, there are only four.
Continuity mistake: When Homer laughs at Patty and Selma, for a few frames you can see that the beer can he was holding is gone. It stays beside the phone for the rest of the scene. (00:07:00)
Suggested correction: When Homer is laughing at Patty and Selma he never has the beer can in his hand. He has a drink then the camera cuts to Marge talking about Patty and Selma, Marge then walks out of the shot, and we get a close up of Patty and Selma. The shot then changes to Homer who starts laughing. Enough time to put the can down.
Continuity mistake: There are three mistakes when court is dismissed: 1) the people standing around disappear, 2) the two men with Fat Tony disappear for one shot, and 3) when Bart says that crime doesn't pay, Marge is suddenly standing beside Bart. (00:20:35)
Suggested correction: There are also 3 corrections here. 1) the only people standing near the bench are Lionel Hutz and Seymour Skinner. Seymour is simply out of shot and Hutz is on screen. 2) Legs and Louie don't disappear they remain standing on the steps but due to the camera angle that is now looking across the steps rather than up the steps so they are out of shot. 3) There is a close up of Bart and Fat Tony long enough for Marge to walk over.
Continuity mistake: Bart puts his lucky red hat on the hat holder. It disappears in the next shot. (00:07:10)
Character mistake: When Homer discovers that the Leftorium is going out of business, there is a sign that says 'Coming Soon: Gum for Less' beside the store. Later on, though, Ned says the new store is becoming 'Libertarian Party Headquarters.' (00:15:50 - 00:19:15)
Suggested correction: The sign is just an advertising poster that's on a wall. It's not in front of the leftorium.
Marge vs. the Monorail - S4-E12
Audio problem: When goes to the Monorail Café, the woman there says to Marge "Go away" but her mouth doesn't move.
Continuity mistake: When Moe tries the Flaming Homer, there are bottles that keep appearing, and the knife disappears suddenly. (00:06:55)
Other mistake: When Bart sees that Santa's Little Helper ate his homework, and the camera moves really fast, you can see that the Krusty Doll and picture frame have vanished from the desk beside his bed. (00:00:55 - 00:01:50)
Dude, Where's My Ranch? - S14-E18
Plot hole: Lisa says Luke was her 1st crush. What about Nelson, Corey, Mr. Bergstrom, Thelonius and the boy that works at the library in 'Bart's Girlfriend'?
Suggested correction: She didn't have much of a crush on Mr Bergstrom, she mainly admired him because he was kind. However you are correct about the others.
Other mistake: When Lisa checks Marge's resume, she reads it and turns it over. But there is no text on the back as there should be. (00:06:30)
Continuity mistake: Homer drives to Moe's Tavern with his normal shirt on. He has his green jacket on top of it in the next shot. (00:04:45)
Cape Feare - S5-E2
Continuity mistake: At the beginning of the episode when we see MacBain on TV he goes through a curtain, the curtain stays open for a second even though he isn't touching it.
Springfield Connection - S6-E23
Revealing mistake: Just after when Marge is reading the book on the sofa she says 'chaos'. On the far left of the screen a large black 'scratch' appears then just slides off.
Suggested correction: I don't see the mistake; I even watched the DVD version, and in the Disney+ version, I don't see it.
Bart's Friend Falls in Love - S3-E23
Continuity mistake: At the beginning of the episode when Bart runs away from Homer, Homer starts rolling down the stairs. The banister disappears between shots. After Homer gets to the bottom the banister reappears. (00:01:40)
Continuity mistake: In the video store, Homer grabs the 'Football's Greatest Injuries' tape with his right hand. He was also holding Maggie with his right arm, so he should have dropped her. (00:06:00)
Itchy and Scratchy: The Movie - S4-E6
Audio problem: Bart's mouth doesn't move when he laughs after saying "Now's our chance to be bad."
Marge vs. the Monorail - S4-E12
Continuity mistake: At the beginning of the episode, Homer slides down a big pipe and smashes through one of the windows on the right side of the car. But when Homer crashes into the chestnut tree, it is fully repaired. (00:01:25)
It's a Mad, Mad, Mad, Mad Marge - S11-E21
Continuity mistake: When Homer is changing the oil in Marge's car, he is in his own driveway, but in the next, he is perpendicular to Flanders' house and then in Flanders' driveway.
Suggested correction: He is in his own driveway the whole time. There's never a shot of him in a different position and certainly never in Flanders' house. You ever see the brick wall from the Simpsons' house in the last shot.
Like Father, Like Klown - S3-E6
Continuity mistake: At the end of Krusty's story, Homer changes from being in his tuxedo to being in his normal clothing. (00:10:10)
Suggested correction: It should be noted that a considerable amount of time has passed while Krusty is telling his story. Note the candles in the screenshot for example, they have burnt out during the story. Its reasonable to assume that there would have been a chance for them to change during this time.
Continuity mistake: When Otto is playing the guitar with bart in the middle of the night, there are close-ups of Otto whenever he is singing. You can see that the wall behind him is plain. However, when there is a wide shot of otto and bart, the wall behind otto has two tables leaned against them. (00:15:50)
