I read about this kind of tactics. Same with Facebook groups - knitting, cooking, history: they start by gathering a mass of normal fans, then slowly turn to the original aim of spreading propaganda. And in this case it was all pro-russian anti-war good-old-communist-times garbage.
My neighbor was a part of a facebook mom's group that went that way. It was a normal group, all the discussion you'd expect, but then the person running the group pretty much took the wheel and turned it hard to the right and even tried testing the locals for their loyalty and etc. Expelling anyone even wondering what was going on and so on. It was wild.