Claire pulls a red tinsel decoration out of a box. After a cut the decoration is silver and a blue one has appeared on the table next to her out of nowhere.
When Cam is playing the ukulele he starts off by strumming using only his thumb but when the camera cut to another shot he strums with his whole hand. A few seconds later it switches back to the first shot where he continues strumming with only his thumb. He would've had no time in between to switch strumming positions.
When Mitch is reversing the Prius, they dub in a sound a transmission with a spur reverse gear would make. But a Prius doesn't have a reverse gear, the electric motor spins the other way for the vehicle to reverse.