Twitter Marks Substack Links as Unsafe, Escalating Hostile Move Against Newsletter Platform

Twitter has escalated its hostility towards Substack by marking links to the newsletter platform as unsafe, despite Substack continuing to work properly. This move follows Twitter's blocking of people who use Substack from embedding tweets, as well as blocking engagement on tweets containing Substack links. Twitter's latest aggressive move is thought to be in response to Substack's own "Notes" feature, which has been seen as a rival to Twitter. Substack's founders have criticized Twitter over the restrictions and rules that "change on a whim". Elon Musk, who has previously expressed anti-competitive views, has not tweeted recently about Substack.