No, the 4chan filter is documented. And I actually think it's a pretty neat feature. Despite being a communist, I'm not quite enough of a left wing radical to want to use it, but I still appreciate what it's made for. But I understand why the radical centrists who made the Lemmy software would see no use for it.

What I really want is an equivalent that bans Xitter screenshots. I don't want to give Musk's Nazi bar any more attention.