r/place 

r/place was Reddit's April Fools joke for 2017. Basically, it was a 1000 x 1000 pixel blank 'canvas'. Anyone with a more-than-a-month-old Reddit account could place a pixel on the canvas in one of 16 colors, but they then had to wait 5 minutes before placing another pixel. The idea was to encourage people to work together and create something.
It was pretty popular, there were a bunch of 'factions' trying to make different things, etc. If you want to know more about that just YouTube search "history of r/place".
r/place was shut down after 72 hours, almost immediately after that remakes started popping up like weeds.

r/place's slogan was 'Individually you can create something. Together we can create something more.'
...problem is, most people just banded together into little tribes. Kinda like life.

r/place by sapodilla June 19, 2017

r/place 

Social experiment carried out by Reddit in 2017 and 2022 (...) around April Fools, where every user could "paint" one pixel every five minutes on a 1000×1000 (and later expanding) canvas. The point of the experiment is creating a highly-competitive environment for people to form alliances and cooperate to "create something more".

My fandom group and one allied group created a picture in r/place, which we were able to defend together until the very end.

r/place by ONG3N April 14, 2022

r/place 

A 1000x1000 pixel canvas where redditors feel they are bonding with one another even though they’ve spent the last three hours arguing over spelling .com as .cum

A: I used to date this ugly, sad, disgusting, short, vile, unfunny, smelly, weak, hairy, boring, creepy cuntbag.

B: He must have had Reddit.

A: even worse! He was a mod of a subreddit for r/place.

B: holy fuck

r/place by king girl coochie April 4, 2022

R.I.P. in peace 

An internet forum term twisting the well known "rest in peace" phrase, possibly originated from Football 365

R.I.P. in peace Fido the dog

R.I.P. in peace by purple_february January 5, 2009