Used in reference to jumping high after getting faked out in a basketball game.
Damn, I had no idea Pete could jump that high! That head fake really put him in the popcorn machine.
A term that can be used to describe a very toxic internet thread.
People associate popcorn with watching movies. Movies are known for being entertaining. A toxic internet thread is known for, again, being very toxic. So toxic, that reading it is like watching a movie, because both are entertaining. Just like what you do while watching a movie, you read a toxic thread, with popcorn. Popcorn comes from either a microwave, or a popcorn machine. Hence, the Popcorn Machine slang.
(Tip: Stay away from them.)
1st person: I really like the song "Minorities in my water park"! Let's read the comments.
2nd person: Don't! It's like a popcorn machine.
1st person: Dunno what you mean by that.
1st person: {reads comments} Yeah, you're right.
2nd person: Told 'ya!