Substack is introducing direct messaging, allowing users to have private one-on-one conversations, the company announced today. DMs can be accessed in the Chat tab on the Substack app and website. By default, users will only receive DMs from people they are connected to. Other messages will go to a Requests folder where you can choose to either accept or reject them. After launching an X (formerly Twitter) clone last year called Notes, Substack is now copying yet another feature from the social ...