When Lainey sees Matthew about to start running, the same extra crosses the same point twice.
When Jake and Lainey are in the lingerie store initially as he sits down, he does not have a glass of champagne in his hand. When the camera cuts back after Lainey goes into the dressing room, he suddenly has a half-full glass of champagne.
When Jake and Lainey came to Xander's house, and Naomi welcome them. The camera panned they raised their glasses. Furthermore, Jake visible wanted to pull down his glasses, but the camera immediately changed and the glasses still on his forehead.
When Xander is calling Jake during the credits, his phone's screen stays on for the whole call.
In the opening sequence, set in 2002, Jake wears a shirt depicting the cover of the Jurassic 5 album "Feedback," which didn't come out until 2006.