resist the urge to make a cohost crossposter
I just don't think it's a good idea
I can say unofficially that for other platforms (tumblr, deviantart, etc.) I'm not 100% opposed to to-cohost crossposters, but I am asking directly that people not make automated twitter-to-cohost or mastodon-to-cohost crossposters. we got rid of the post length limit for a reason and that reason is that microblogging is a scourge.
it's also fine if you want to crosspost threads or even single tweets/toots by hand! but please think critically about why we didn't just fork masto in the first place.
edit: @ThePhD pointed out that this wasn't clear in my original post, but I consider PostyBirb to be one of the good kinds of crossposters; if you're making and posting stuff like art that works on all platforms equally, then crosspost away.
but text posts on twitter are so heavily constrained for the sake of a design decision that has long since been abandoned, I still stand by my belief that generically crossposting twitter/masto to cohost is a bad decision.
we got rid of the post length limit for a reason and that reason is that microblogging is a scourge.
I chose cohost specifically because I think microblogging is just a net bad, and "microblogging but it's on a different server" is not any less bad.
You do you, I'm not gonna block anybody for twitposting, but I personally have felt a palpable relief in the ability to stretch my legs and actually complete a thought, and with that came a sense of freedom from the pressure to constantly post my own half-conceived takes on everything.
Give it a try, it's kinda cool to have a conversation again.

