Some good points here, though a couple are outdated too. For instance, I'm not sure I'd recommend mailing lists in 2018, since they're simply less convenient for the average user than a good forum might be.<p>That said, one extra piece of advice that should be added for a future version of a list like this is as follows:<p>Do not use a chat system as your only support channel.<p>Seriously. Things like Slack, Discord (and open alternatives like Riot) are not good systems for support forums, or any sort of community that should be visible by the public. They make it impossible to find answers with search engines like Google, impossible for archiving services to back them up in case things go down and force users to register to simply find any help given to others.<p>They're terrible systems for this purpose, and should not be used as a primary support channel for a project.<p>That's another piece of advice for such lists right there.