Continuity mistake: At the saloon, Jim brushes off Mr. Walsh and walks out on him. Walsh turns to Francie the bartender, who suddenly is holding the bottle that was undisturbed on the counter a moment before. (00:17:25)
Continuity mistake: When Sylvester produces a piece of bubble gum, the writing on the wrapper in long shots says "Gum", but in close-ups it reads "Bubble Gum".
Continuity mistake: During the rehearsal, Bixby throws a temper tantrum and kicks the piano. It slides straight toward the curtain, but in the next shot, it's spinning around. In the shot after that, it disappears altogether. (00:26:10)