Continuity mistake: During Fred's dream sequence, Fred tells Barney that he missed watching Pebbles and Bamm-Bamm grow up and behind Barney there is a table and a painting on the wall. In a close-up of Barney in the next shot, both the table and painting have disappeared.
Continuity mistake: When Fred and Barney discover that the football match on TV has been postponed, we see an interviewer sitting at the desk and you can see there is a nameplate saying "T.V." in front of him, but when the interviewer introduces Eppy Brianstone in the next shot, the nameplate has disappeared.
Continuity mistake: Before Mr. Slate takes a picture of his employees, Sandy (the one that Fred gives a hot foot to) is standing by two other men. When Fred gives Sandy a hot foot, the men have disappeared, and when we see the photo that Mr. Slate has taken, they are back again.