I’ll go first: r/kitty. One of the hundred grillion cat subs back on Reddit, the culture in this one was you posted a cat picture, and the only word allowed in the title or in any comments or replies was “Kitty.”
Someone is using that subreddit for covert communications, I just know it. Either on the level of “if u/PM_me_your_nostrils posts an orange cat, we attack at dawn!” or there’s some steganography going on with the pictures, but that subreddit was too stupid to be as active as it was.
“We oppress minorities to scare them away” is hardly a novel tactic
It might be one of the oldest type of conspiracy, that humans created when societies started to be a thing.