Markdown in Drafts to Rich Text email

On my Mac: Either via a set of Drafts actions, Keyboard Maestro or some other method, I’d like to write an email in Drafts that I can format a bit using markdown (bold, italic, lists) and then send via Postbox (my default email client) as rich text.

Sending via Postbox is easy - Drafts has a Mail action that works on MacOS. But that action cannot output as HTML on Mac.

I can’t figure it out! Help!

It sounds like you probably want to use Drafts’ Mail Assistant for Drafts. It’s purpose is to allow Drafts to send formatted mails on the Mac.