How to get Thunderbird to nicely format Markdown?

Solution 1:

Source Markdown Here 2.11.4

Markdown Here lets you write email in Markdown and render it (make it pretty!) before sending.

This is great for anyone who doesn't like fiddling around with formatting buttons while writing an email. It's especially good for programmers who write email with code in them -- it even supports syntax highlighting. And for the mathematicians among us: Markdown Here will render TeX formulae as well.

Totally simple to use:

1. Write your email in your email client's rich editor using Github-flavoured Markdown.
2. Right-click in the compose area and then click "Markdown Toggle".
3. Your email is now pretty! (That is, it's been rendered to HTML.)
4. If you like the way it looks, just send it. If you want to change or add something, click "Markdown Toggle" again to get back to your original Markdown.
5. Repeat as necessary.

Disclaimer: I've never used Thunderbird or Markdown Here.

Solution 2:

There was a Markdown Viewer extension to Thunderbird once, but according to the reviews it stopped working at some point and is certainly no longer usable after moving Quantum / WebExtensions.