The Nightmare After Krustmas - S28-E10
Continuity mistake: When Homer moves Maggie's crib closer to the gnome, the wall outlet under the light switch has nothing plugged in, but in the next shot as Homer exits the bedroom, a nightlight is suddenly plugged in. (00:10:20)
The Nightmare After Krustmas - S28-E10
Continuity mistake: While Krusty is in the hospital talking to Sophie, he pops the IV line from his arm so the tubing hangs down from the fluid bag. But when Krusty tells Sophie that he knows she's reaching out, suddenly Krusty's IV line is properly inserted in the cannula again, only to change back to the tubing hanging down. Also, the white pillow propping up Krusty's foot vanishes and reappears during these shots. (00:05:15)
The Nightmare After Krustmas - S28-E10
Continuity mistake: When Bart opens the door for Krusty and Sophie, Bart is standing on a floor mat, but in the next exterior shot, that indoor floor mat has vanished. Other changes include the cane's handle within Krusty's grip facing the opposite way, as well as Krusty's and Sophie's positions at the outdoor purple mat. (00:06:50)
The Nightmare After Krustmas - S28-E10
Continuity mistake: When Krusty is at the hospital, in the first shot, Krusty's IV tubing is attached to the fluid bag over the bed's safety rail, but in following shots, the tubing is inserted between the rail bars. (00:04:00)
Continuity mistake: After Homer reveals the secret ingredient, one week later, Homer walks into Moe's. In the exterior shot, the door swings open at its right. However, when Moe lights the Flaming Homer, in the next exterior shot, the door swings open at its left. (00:21:00)
Continuity mistake: When Scratchy's head gets sucked into the dam pipe, the back of his head goes in first, but when he is shot out, he is facing forward.
$pringfield (or How I Learned to Stop Worrying and Love Legalized Gambling) - S5-E10
Continuity mistake: When Marge enters the bedroom, the family appears from behind the mattress, and Maggie's outfit is her traditional blue, but when Marge picks her up her outfit is white. (00:17:10)
Audio problem: When Laura insults Kerney and Dolph, Dolph speaks but it's Jimbo's voice we hear even though Jimbo isn't there. (00:05:50)
Continuity mistake: Lionel Hutz runs out of Burns' office leaving both doors open. When Marge says about going, they are closed. (00:20:20)
Continuity mistake: When Homer is talking about Marge getting a job at the dinner table he has a spoon in his hand. Once Marge has finished scowling he doesn't, and there isn't one on the plate either. (00:08:05)
Homer Alone - S3-E15
Continuity mistake: When Marge has finished the list of things to do at Rancho Relaxo she has a list on the bed. When we next see Marge a few seconds later, the paper is gone. (00:17:50)
Revealing mistake: When Homer leaves the bar after the Superbowl, as he goes through the door, the background is missing. It's just a brown background. (00:20:00)
Continuity mistake: Just as Barney asks Homer if he wants to go bowling next Sunday, Moe's boot disappears from the bar and the money appears in Homer's hands off the bar. (00:12:20)
Continuity mistake: When Homer gets off the phone to Moe, all the snacks he had have simply gone beyond a few remaining bits. (00:02:00)
Radio Bart - S3-E13
Continuity mistake: When Bart realises he left a "Property of Bart Simpson" label on the radio we see the camera zoom to the well and down to the radio. However at the top, all the fun fairs, stalls, police tape and people have vanished. (00:14:50)
Continuity mistake: When Homer leans back the lamp next to him changes from a red freestanding one to a blue table-top one. (00:02:40)
Continuity mistake: At the bar when Homer is watching the superbowl, his hands keep changing position between the shots. (00:19:00)
Some Enchanted Evening - S1-E13
Continuity mistake: When Marge and Homer leave for dinner, there is a lipstick mark on the back of the door. The lipstick mark is from the scrapped pilot version ("the Butterfield Incident") in which Homer slams the door on Marge as she tries to kiss him. Some of the animation cells were re-used for the version that ultimately aired on Fox.
Itchy and Scratchy: The Movie - S4-E6
Continuity mistake: When Homer is about to punish Bart, his ticket suddenly appears in a shirt pocket. (00:15:10)
Continuity mistake: The position of the video in the basket changes between the first two consecutive shots. (00:04:50)
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.