Continuity mistake: When Fez knocks the clown over and shatters it, you see the head roll in front of the body and out of frame with the nose still attached. Donna then turns around and runs in to take the nose from behind the body of the clown.
Good Old Fashioned Lover Boy - S8-E11
Continuity mistake: While St. Christine and Jackie speak about honesty, the brownies in Jackie's hand suddenly switch to Christine's hands in one shot, then return. (00:20:05)
Continuity mistake: When Hyde enters the scene, his shirt is somewhat tucked behind his belt. In the following close-up shot his shirt is above the belt but returns to the tucked position in the next shot. (00:00:10)
Answer: It's Ashton Kutcher's dog.