Other mistake: After the Grinch steals everything from the first house, when he drops all the bags on Max, the ties around the bags change from light brown to dark brown twice. Additionally, the bags ever so slightly change position the second time it happens.
Other mistake: When the Grinch slides down the chimney to the first house, part of his Santa suit and his hat flash green repeatedly.
Other mistake: When the Grinch tells Cindy Lou Who, "I'll fix it up there, then I'll bring it back here," when he says the word "back," his right cheek briefly turns white. Then, when he says the word "here," part of his left sleeve briefly turns green.
Other mistake: After the Grinch sends Cindy Lou Who to bed and closes the door, part of his Santa suit becomes the same colour as the background mid-shot.
Other mistake: When the Grinch runs to the top of Mount Crumpit and grabs the sleigh, a part of the sleigh disappears for a frame or two.
Other mistake: When the Grinch rides his sleigh back to Whoville and returns everything, as the narrator says, "He brought back their pantookas," a pink ornament lands on the Christmas tree, then changes to yellow mid-shot.
Other mistake: When the Grinch is cutting Max's antler, the pieces that have fallen on the floor suddenly jump several inches closer to Max.