Mastodawn

I'm obviously old. what is this "rule" trend I'm seeing everywhere on Lemmy?

As per the title. I’m obviously an old Bustard. Somebody please explain Rule to me.

Thanks for asking OP, I had no idea either.

I know on Tumblr it means 'if you laugh you have to reblog', but judging from the posts on here I didn't think it was the same