The cookie that Deena put down on the counter is shown with a broken piece in the shot of over Jess' shoulder. Then the cookie is whole again in the next shot over Deena's shoulder. Then in the next shot over Jess' shoulder, the cookie is shown with the broken piece again.
During the dinner scene with Jess and Alex, Jess takes a sip of her wine and places the glass back on the table, which causes the wine to move in the glass. In the next shot, the wine is completely still like the glass was never moved. And then in the next shot, the wine is slowly moving after being placed down.
When Jess and Deena are having a conversation about Sara and Tyler in Deena's kitchen, Deena stirs her drink with a spoon and in the next shot, the spoon is instantly gone and the position of Deena's hands change when she says "You can shut your door, and you can sterilize your kitchen, but you can't put Sara under the glass". There's no way she could of removed the spoon or change the position of her hands that fast during the conversation.
As Deena and Jess are having a conversation about Sara and Tyler in Deena's kitchen, Deena breaks off a small piece of her cookie and puts it down. In the next shot, she puts it down again.