Factual error: When Amy is fired from S'Nuff magazine she takes her story on Aaron Connors to Vanity Fair, who run with it. That is not going to happen. Amy wrote the article while a paid employee of S'Nuff magazine and that means the copyright in the article (and, very relevant to this issue, the photographs of Aaron they paid to have taken), resides with them, not with her. It isn't hers to sell. No magazine editor of any standing is going to buy an unsolicited article without checking its provenance backwards and forwards, and that would mean checking with Amy's previous employers - after all, what would happen if they changed their minds and ran the story themselves?
Factual error: The main character from the video game "Paperboy" is among the alien invaders in the final battle; since that game was first released in 1984, he shouldn't be there, because the probe the aliens received featuring video game footage was launched into space in 1982.
Plot hole: Joy and Sadness are stuck outside of the control center. They are trying to figure out how to get back, and encounter maintenance workers who are discarding old memories. The maintenance workers show that they have the power to send memories back up to the control center to be played. Why couldn't they send the core memories that Joy had back up the same way? Better yet, why not use that method to send Joy and Sadness back up to the control center? The director of the film is even aware of the plot hole, and said "Yeah, well then we wouldn't have a third act," before explaining how the idea of recalling memories was added in later, "box[ing] [the screenwriters] in a corner a little bit."
Suggested correction: Even if they do send the core memories up to headquarters, they wouldn't be able to get joy and sadness through the tiny gap that the workers send the memories up. Joy has to be in headquarters for Riley to be happy.
This mistake is large enough that the director is aware of it. I think that more than qualifies it to be on this site.
Suggested correction: Joy is a control freak, she wants to return the memories herself. She doesn't even imagine that the workers can do such a thing.
Other mistake: When Rusty is talking to the trucker on the C.B. radio, he hands the microphone to Kevin. Kevin never presses the talk button on the microphone when he is talking to the trucker.
Continuity mistake: When Anne Hathaway is showing Robert De Niro how to use Facebook, she pulls her phone out of her pocket as she asks if he has a photo of himself. When the shot changes for his answer, she pulls the phone out again. (00:53:20)
Plot hole: In the beginning, vampires are shown to be invisible in photos but then they seem to appear in videos like security footage and social media posts.
Other mistake: Two cars with the same license plate numbers are seen as the minions are hitch hiking on the road. The plates of the hippie wagon and the old lady's car both read D-6413.
Continuity mistake: When SpongeBob says he should sacrifice himself, the squidosaurs Rex has Mr. Krabs in his hands, but when SpongeBob walks to the counter, Mr. Krabs is right next to Squidward. When the camera zooms in on a group of citizens and Squidward, Mr. Krabs is gone. Then, another shot of the squidosaurs Rex, Mr. Krabs is in his hands again.
Other mistake: Catherine lives in apartment 1 on the first floor, but she goes in to apartment 4 on the second floor and right in front of Neil's apartment. (00:06:26 - 01:10:28)
Continuity mistake: When they visit Morgan Freeman at his office the yellow handkerchief in his jacket pocket appears and disappears frequently.
Continuity mistake: Bradley Cooper has dried blood running down his face just after he sends the meals out to the star diners. Then in the next shot he rubs his sore eye - all the blood is cleaned up and it's a tiny smudge. (01:14:20 - 01:14:55)
Continuity mistake: James and Darnell fall from the boat and get soaked, yet they are barely wet when they climb back on board.
Continuity mistake: When the waiter picks up the tray with the poisoned drink on it, it also has a bowl of fruit. When he gets to Rayna's table the bowl of fruit is gone. (00:55:20)
Continuity mistake: When Anna Kendrick is making pancakes for her friend, in a shot of her from the front she isn't wearing her necklace, but in the second shot it shows her wearing it again. (00:24:35 - 00:26:15)
Character mistake: When Gaby's car becomes wedged between two buildings, she says, "Good plan. All we have to do is get over two twenty-foot walls and a minefield." While minimal backstory is given, I think it reasonable to assume that she has lived in what was East Germany all her life. It is thus highly unlikely that she would express a measurement in English units (being bilingual doesn't mean you automatically convert measurements). She would have said something like "six meters."
Continuity mistake: When Maya is trapped in the bathroom and the bad guy breaks in, she drops her pepper spray which you can see lying on the floor when the bad guy is talking on the phone. Shortly afterwards it's gone. (00:47:35)
Continuity mistake: When the Bellas just got told that they are not allowed to compete any more they walk outside and Beca gets a call. When the camera is zoomed in on her you see her calling and moving a lot. When the camera is focusing on the other Bellas she is standing completely still in the background. When the camera is back on Beca she is moving again. (00:12:50)
Continuity mistake: Charlie Brown is using a pen to write a book report. The black ink leaks and gets all over his hands. When he walks to his dresser to get a pencil, all the ink stains are gone.
Suggested correction: He wipes the ink on his shirt.
Plot hole: The ending that Zach wrote was that all of the monsters got pulled into the manuscript but, Brent Green, the Invisible Boy, somehow managed to avoid being captured even though he should have been sucked in too.