Continuity mistake: During the Green Day concert, the lyric displaying teleprompter sits onstage beside the mic stand, but then disappears, reappears and disappears again by the time the barge sinks. (00:03:10)
Continuity mistake: At the end when everyone is congratulating Homer, Comic Book Guy is by Homer. Homer then rides down the street to Marge and Comic Book Guy is suddenly by Marge. (01:13:05)
Continuity mistake: When the family move to Alaska, the door to their cabin opens to the left (looking at it from the inside) when Homer escapes from Bart and Lisa's "avalanche". But later in the film it opens to the right (from the inside). (00:46:25 - 00:52:05)
Other mistake: When Homer is collecting firewood his footsteps start randomly in the midde of nowhere, with no tracks to the trees he came from. (00:45:55)
Continuity mistake: In the scene where everyone is climbing the rope to get on the top of the dome, Homer should already be at the top, but when the camera points to the top of the dome, he does not appear there. The next scene shows him back at the top of the dome again. (01:05:15)
Continuity mistake: Eddie and Lou are at the lake making notes about the Pig Crap Silo. The next shot is of the town approaching the Simpson house and Eddie and Lou can be seen in the mob. (00:30:50)
Continuity mistake: When Homer circles the dome on the bike, in the first two shots (close-up and wideshot) Homer's left hand is gripping Bart's left wrist, but in all of the following shots it is Homer's right hand that is gripping Bart's left wrist. (01:12:50)
Continuity mistake: The clock on the bomb instantly jumps several seconds despite instant cuts. It goes 17, 16, *instant cut* 11, 10. (01:09:40)
Continuity mistake: The door to Homer's cabin in Alaska changes positions, from facing the street when he comes home from the bar to facing over a cliff when he decides to follow Marge and the kids back to Springfield. (00:46:25 - 00:52:45)
Continuity mistake: When the wall is put up around the lake it is built right next to it, but when Homer dumps the silo the wall's much further away from the water. (00:21:15 - 00:24:05)
Continuity mistake: Barney runs head first into the dome and slides down horizontally. Next shot he is stood up and is shoulder barging the dome. (00:48:10)
Continuity mistake: When Homer is on the wrecking ball, he hits a fork on one side but in the next shot it vanishes. (01:01:00)
Continuity mistake: When Homer tells Lisa to clap in Alaska, there is some snow on his left ear that moves to the top of his head. (00:46:05)
Character mistake: The mob is marching to Homer, however they are going the wrong way. In the mob we see several people who all know where Homer lives. So why march the other way? (00:31:40)
Continuity mistake: When the dome is placed over Springfield, you can see Lenny and Carl in the middle of Springfield. When the dome goes over Moe's and the Church, Lenny and Carl are also at Moe's. (00:25:55)
Continuity mistake: When Russ Cargill spreads the five unthinkable options on the President's desk, the book's spines are all facing to the left, but after the President chooses option three, in the close-up the spines are facing to the right. (00:26:40)
Continuity mistake: When Homer is eating a krusty burger you can see crumbs on his face, but in the next shot of him talking the crumbs have vanished.
Other mistake: At the end of Marge's video message to Homer, Marge explains she taped the message over their wedding video. The video then shows the remainder of Homer and Marge's wedding. This is inconsistent with The Simpsons' Season 3 episode "I Married Marge" and Season 8's "A Milhouse Divided," which show Homer and Marge marrying at a chapel on the state line and later Homer and Marge alone eating cake together in a parking lot.
Continuity mistake: When Marge is in the kitchen trying to figure out the meaning of "a thousand eyes", behind Grampa there are three spoons hanging from hooks, but when Marge tells Homer that the warning in church was about the pig, the spoons have vanished and instead there are three cups hanging in their place.
Continuity mistake: When Marge is in the kitchen with Grampa wondering what "a thousand eyes" can be, over the telephone there's a notepad with writing hanging from a clip, but when Homer walks in with the pig the notepad is hanging from a string and the writing has disappeared, but then it switches back again.
