Continuity mistake: Season 4, Episode 15, "Anchors A-Warners": When a disguised Dr. Scratchansniff is in the cruise ship's cabin searching high and low for the Warners, the bed's pillow changes location between shots. After he tosses it on top of the blue blanket, the pillow suddenly returns to its original location beside the headboard.
Continuity mistake: Season 4, Episode 8, "Jokahontas": After John Smith's recruits demand the ice cream recipe, Yakko holds it at his side and claims that it's a trade secret. But once the shot changes, the recipe is gone.
Continuity mistake: This concerns Pinky and The Brain's second intro: when Pinky runs in place on the hamster wheel and asks Brain what they're going to do tonight, Brain holds one cage bar, then two, between shots.