Yes, this was in 2017/2018, ex-admin "BATISTUTA9" created a Chrome extension called "HLTV.Pro". It came with a boatload of cool features: A karma system, the ability to see previous flags the user had equipped at one stage, a HLTV Chat and the ability to block users...
As you can imagine, I am all for users having interactive functionality but the two functions not utilised correctly were the block function and HLTV Chat.
HLTV Chat was frequently hacked by users messing with inspect element, impersonating and pretending to be other users. What started out as a great little personal chat service to interact with other users from HLTV turned sour and I was quickly casted out due to users impersonating me on HLTV Chat.
Blocking users went about as well as you would expect... Users were blocking each other for simply having a different opinion, no discussions were being had and you could still see the replies of users who blocked you, they just couldn't see yours. This led to topics being made to merely express basic points because they couldn't defend themselves and defamatory, guestbook entries were also being spammed out of protest for being blocked.
Complete anarchy, friend. To this day, I feel awful for BATISTUTA9 who poured his heart out into an extension only to have users abuse the hell out of it.