Continuity mistake: Dale is standing by the couch with the towel in his right hand, but in a shot of Jack getting mad, the towel is in his left hand, but back in his right hand in the next shot.
Continuity mistake: On game night when Jack hands Hans the soy dipping sauce, Hans puts it on the left side of the plate. When the shot changes to Jack walking away, the sauce is on the right side.
Continuity mistake: When Jack comes in, he slams his drink down on his desk behind the cup and to the left of his briefcase. In the next shot, it's sitting to the right of his briefcase by the edge of the desk.
Continuity mistake: The position of Heather's hand on the soda can changes when she takes a sip.
Continuity mistake: When Jack grabs the bag of hair, he grabs it so his fingers are over the hairs. But in the next shot, the hair is on the other side of the bag, away from his fingers.
Continuity mistake: The way "Jack Griffin" is written on the board changes in various shots.