Continuity mistake: When Catherine and Jimmy are talking in the break room, after Catherine gets done telling her story there is a pile of napkins on the counter the top - one is folded. When Catherine and Jimmy hug, there is no longer a folded napkin on top.
Continuity mistake: When Bill is pretending to be Matthew and he falls off the chair he knocks over his coffee mug and Lisa reaches to put it upright. The shot changes and it is already upright. Also there is nothing in it, he then picks it up and leans back in the chair and falls again, and coffee comes out.