Other mistake: In late evening a messenger boy riding a bicycle stops across the street from Harold's house. As he turns the handlebars toward the left, the bicycle light shines through the front window of Harold's house. However, in the close-up of the window, the light is shown moving from left to right. It should be moving from right to left.
Other mistake: Throughout the movie, Harold Lloyd's prosthetic glove on his right hand is noticeable in the wideshots when he stretches or holds out his right hand, so in all the closeups showing both of Harold's hands it's the stand-in's hands we are seeing.