Other mistake: After the magnet grabs Slink during the incinerator scene, all the toys grab metal objects to avoid getting torn up. Afterward, they all let go of their metal objects to drop down. However, Slink also drops down despite not holding on to anything because he is made of metal.
Suggested correction: Or, the other toys helped him down.
Other mistake: Before the battle, the leader of the waterbenders says that he will have everyone extinguish as many sources of fire as possible. When the firebenders come up from the ground at the start of the battle, all of the torches lighting the city are lit.
Other mistake: When the ride finishes, there is no sign of a safety bar in Gru's cart.
Other mistake: When Gregory has read the note from Fregly, he realises he put his thumb on a booger. When we see Greg on the floor, the note should be nearby. Instead it is several feet from him, in line with the bin. This is strange as Greg only dropped it and the note didn't flutter over there as Greg only turned when he hit the floor. In fact, the movement should've moved it closer to him. In line with the bin is even weirder.
Other mistake: Flynn and Rapunzel go through the Snugly Duckling tunnel. Later when Maximus points to it, you could easily see it from anywhere in the pub. But nobody saw Flynn and Rapunzel go through other than the thug who showed them.
Other mistake: As the movie opens, Yogi is using a telescope to watch a family at a picnic table. The reflection in the lens should be in reverse but it is not. It shows the same view.
Other mistake: In the beginning of the film, when they are showing Dre's "growth chart", it shows about 2.5 inches of growth between April 2003 and May 2003, which is not possible. And no, there is nothing in the movie that indicates he has some sort of abnormal condition that causes rapid growth.
Other mistake: Eustace's diary seems to be perfectly fine as he was making entries on board the ship despite it being fully exposed to the sea water.
Other mistake: The protagonist is still a kid, and she is telling in voiceover about all the things she vows to renounce hoping to have her dad back in health. On the porch she knocks repeatedly on the wood, but the magical numbers don't appear. (00:05:00)
Other mistake: The huge amount of toothpaste on the cat's head manages to disappear completely in a nano second, with the mere lick of his tiny tongue.