Twitter's new policy bans the free promotion of certain other sites, such as Mastodon, Facebook, Instagram, Truth Social, Tribel, Post and Nostr.
https://www.rollingstone.com/culture/culture-news/elon-musk-twitter-mastodon-instagram-facebook-1234649511/
Elon's New Twitter Policy: No More Links to Rival Sites

Even posting screenshots of account handles for sites like Instagram and Mastodon is a no-no

Rolling Stone
@RollingStone well that makes Twitter completely irrelevant in many cases. When does the bankruptcy proceeding start?
@RollingStone I’m here because he’s there
@RollingStone: Please don't just parrot Melon's words which he used in unusual ways as though they had their ordinary meanings. At the very least, put double quotes around "free promotion".
@RollingStone Will he continue to boast of being a liberal?
@RollingStone What a thin skinned little baby. He's literally afraid of freeware.
@RollingStone Well I guess we know what to do then…..
@RollingStone Did not realize this when I joined this site earlier today and posted where to find me on the Other Place. Haahaaa, cancel me!