The code of conduct here is pretty straightforward. Don't be a jerk. Don't make fun of people. Don't make other folks feel bad about themselves. Generally, just be polite when talking with other people! I think that covers roughly 99% of the usual garbage that arises online (hate speech, bigotry, Nazism, trolling, etc.).
One more thing: I'm about as pro free speech as they come, but if you start espousing militant political propoganda and I catch wind of it annoying others, I will have to ask you to stop or to leave.
Thanks for helping make OpenWeb.social an awesome instance, and feel free to ping me if you have any questions! –@jared