Memes that are usually never funny even the first time people make them and used solely for the purpose of being made over and over 'till people are sick of hearing them, like putting cold food on a microwave, hence the "microwave" part. First told in a lyric by Kendrick Lamar's song N95 where he said the word to express the staleness and cheapness of reused social media memes
"Take off them fabricated streams and them microwave memes, it's a real world outside (Take that shit off)"
A bullet reply is basically a reply that you say on social media when you really want to diss someone who said something that irritates you but you don't want to go too over the top so you don't seem too butthurt. The bullet part is an analogy, basically think of how a bullet is small but it can kill someone just fine. That's basically it, you send a reply that's not an over the top insult, but it gets the job done just fine
Person 1: Damn this guy irritated me
Person 2: Did you ignore him?
Person 1: No, it would be best to do so, but I sent him a bullet reply instead
Person 2: Good shit, that'll teach 'em
Crowd hopper is a person that has an opinion at first but then immediately switches up when he sees the majority saying an opposite opinion to theirs, they're "hopping" with the crowd. These people are usually bad friends or are in a friend group consisting of bad people, and always call them out when they do this shit.
Person 1: I can't believe this, I thought me and my friend agreed that you don't need to have meta characters in gacha games to be good, but as soon as his friends told him otherwise he immediately switched up
Person 2: Wow what a crowd hopper