Chick brings the window to Norma's house, they tear the plastic covering off, but when Chick goes to leave, the plastic is covering the window. Next moment the plastic is back to being torn off.
Chick uncovers the glass when talking to Norma, but later when he has left it is covered up again, then uncovered while Norma talks to Alex.
When Norma is talking to Chick in the diner, the orientation of the handle on Chick's coffee cup changes several times, including while he is holding it in his hand.
When Alex comes home for dinner, he takes off his jacket and sets it in his chair.
When the camera switches to Norma, then back to him, his jacket is back on.