OK this may be too picky but I just accidentally came upon it. During the scene where Shrek is asking the donkey who Fiona was talking about when she said "ugly" he says who was she talking about and donkey says why don't you go ask her yourself then Shrek hits his head and says "the wedding". When he does his ear disappears and comes back after he moves his hand. It doesn't move with the hand like it should.