I could share even older story, it was on kinda forum, kinda not the place is quite hard to describe, but let's say it had these "threads" or "rooms" people discussed in long periods of time instead of making new topics.
So I was hanging around in some fandom threads at the time and I heard from my friend that people used this one thread for off-topic discussion on whatever and said I should check it out too. Well when I finally did, for my surprise I found that the topic just the moment I decided to check it out was myself and not in flattering manner, there was this one guy who I didn't agree in lot of things, but thought we had just difference of opinion and still were friendly, just talking smack about me. So of course, I couldn't just close the tab and pretent I didn't see anything- I had to make post myself. Saying like hey I heard this was nice place to discuss all kinds off-topic stuffs, my friend who is regular here recommended it and said everyone is nice here - and BTW nice that you are talking shit about me here, especially when I haven't talked to most of you before and don't have any problem with any of you. The awkward thing was, that all the mods were in there too and some were also spreading rumors of me although I hadn't even talked to them before that. Awkward.
Then for another, this was on gaming forum. So there was some character threads that people had highjacked to discuss about off-topic stuff, sth that mod know about, but didn't really care since people were having fun. But the weird thing is that this popular thread I used to go in and that had lot of regulars was also attacked multiple times. Not by other users, but actually there was organized attacks via tumblr, people would pick time and make tons of alts with ip changers and just flood the thread with disgusting porn and get it closed. This happened couple times actually. Like if you think kpop fans are petty and full of drama, you haven't seen anything about gaming. That shit gets weird.