Ollie opens the oven door, leans across to get a chair, and in the next shot the oven door is closed.
The amount of stove chimney soot on Ollie's face and coat changes from when it first happens to the next shot.
Ollie visibly shuts his eyes in anticipation several seconds before Stan blows soot in his face.
Ollie throws a flowerpot through the window. It goes sailing through the house and out the opposite window and hits a gardener on the back of the head. However, right before it hits, a hand on the right side of the frame can be seen throwing the pot directly at him.
Ollie throws a flowerpot through the window. It goes sailing through the house and out the opposite window. As it breaks the glass the wire/rope that has it tide to the window frame is clearly visible.