It was at the height of the Glimmergate drama last year. Basically this British user the board nicknamed Nigel started sperging out and going on rants about how the site was infested with Starlight Glimmer fans, whom he referred to as "Glimmerniggers." He complained frequently and obnoxiously enough that people started posting pictures of Glimmer and threads about Glimmer (btw you'd best start believing in Glimmernigger threads anon…you're in one). This of course made him sperg even more to the point where "Glimmerniggers" became a self-fulfilling prophecy and the board was being shit up with Glimposts and posts by Nigel sperging about them. Eventually it got bad enough that mods had to step in and start warning/banning people for deliberately triggering this one autist, so threads about Starlight Glimmer, particularly ones directly referencing Nigel or Glimmerniggers, were effectively banned for a while.
The controversy has recently started again because of two threads started by Nigel in order to shill some fanfiction he wrote. Hence this ancient history thread getting a bump.