To give you the 101: the actor of the clown went on to play Chuck in Better Call Saul. Chuck at one point went on a rant about the misdoings of his little brother, Jimmy. Jimmy once had an incident with a certain car's sunroof.
The meme really is a lot better if you've heard the rant before (major spoilers for Better Call Saul): youtube or piped
I loved that show because I identified w jimmy as someone whose ambitions/aspirations where openly thwarted by those he cared about and was devoted to but kept the open secret from him. I hated chuck because it was clear he was acting on a desire for familial revenge; but then the writers in the last season made it clear that Jimmy is always in the wrong so now I just have ambivalent feelings about a show I loved and then deeply hated in the last 3 episodes
It's one of those things from BB/BCS that is a very pivotal dramatic moment in the show but subsequently got memed to death, so the connotation in online use is generally different from how the scene was played. Same story of that short of Walter White falling over in Ozymandias.