Droopy's Double Trouble (1951)

Continuity mistake: When Spike says "Let me have it, pal!" he is holding a knife, fork and a plate and has a napkin around his neck. But when Drippy punches Spike, he goes back into a veranda and the napkin, plate, knife and fork have all disappeared, and when Spike crashes back into the door, the napkin, knife and fork have re-appeared.