Why is there no email client based on Markdown?

Probably there is a limited market for it, but at the same time you wouldn't need to do much to support it in most of the major console-based clients.

Back in the day I wrote a modal console-based mail reader, which was much more flexible than the alternatives at the time (mutt, pine, etc).

I wrote the core in C++ and used Lua for the UI and all scripting stuff. The user-interface, processing filtering, hooks, etc, were all based on lua and it was pretty good, and extremely quick to use if you had it setup like you wanted.

But to go back to the topic a lot of the console clients, such as mutt, use "mailcap" files. They allow you to filter the content of messages based on mime-types. So adding the ability to read/send markdown would be trivial.

text/markdown could be piped through a markdown to HTML converter, or displayed raw. Similarly you could add a text/markdown header to outgoing mail and just write .. markdown .. in your editor.

But most people wouldn't care, because most people don't even use console based mail clients any more. I gave up myself after having a virtual machine and reading mail over SSH for 20ish years. Nowadays? I pay for google workspace for myself, my virtual machine is long-since dead and I don't self-host anything myself in the cloud, just in my house where I have a NAS, backups, and stuff.

Markdown is great. I use it all day, every day. But, email clients are mostly targeted toward general users. General users don't know what Markdown is, don't know how to use it, and don't want to use it.

General users want WYSIWYG. There's nothing wrong with HTML. It is the predominant standard and along with CSS, very expressive.

From the horse's mouth: "the single biggest source of inspiration for Markdown's syntax is the format of plain text email."

Send plain text emails. Use * and _ to emphasize things. This was something people have been doing for damn near 50 years now.

How should it work? Should it only render emails written in the Markdown format and fall back to raw text for html emails? Given that almost every email nowadays is HTML, it would be a pretty useless client.

Markdown is more of a data cleanliness concern, keeping your markup simple and parseable. But because email had WYSIWYG GUI clients dating back to the 90s, there's too much entrenched inertia to change it now. Adding Markdown parsing would be pointless because nobody composes emails in Markdown when they can just select text and make it bold, etc., right in the GUI.

Not sure if this is exactly what you mean but Buttondown is Markdown-first: https://buttondown.email/features/markdown

How do you implement advertising analytics and user surveillance with markdown?

What's the need? Every email client can already do what Markdown can.

> And on a sidenote why are there no beautiful AND well working email clients out there?

I'd say Thunderbird is a pretty good email client

Email clients are still stuck in the 90s the way they render HTML, good luck asking them to render Markdown ;)

You can make!

Usually markdown generates HTML. If a Markdown email application doesn't generate HTML from the markdown, what should it generate? Good luck.