So the markup dialect that's widely used but suffers from a near-total lack of viewers will now finally be rendered as intended, at least on Windows?
Markdown presents a chicken-&-egg scenario that has dragged on for decades: tons of Markdown documents, but almost nothing with which to simply view (not edit) them as intended. Mystifying.
The point of markdown is that it is human-readable not only in "rendered" html form, but plain text too.
I think this explains the lack of viewers; they are simply not needed.
That doesn't explain it since that point is theoretical, in reality markdown is poorly readable even for the basics (table with a few bold red words in a cell easily breaks alignment / readability)
(also seeing all those marks isn't aesthetically good, hence the need for a viewer)
At this point I really think GitHub should formally publish their flavor as well as a default implementation. It's likely the single most widely used variant online at this point.
I know there are others and there are fine points. I would like to see a couple minor additions to support image placement (that aligns with Medium's editor) and finally a strike-through text notation. But that's about it.
Github does publish their spec: https://github.github.com/gfm/ The CommonMark spec is largely based on it.
https://github.com/rabfulton/ViewMD
Markdown viewer for Linux
PowerToys had a Markdown renderer for the Preview window added in version 0.16.0, which was released around late March 2020.
I used to write documentation in Markdown manually. About a year ago I started using a VSCode extension to tell me if there are minor errors in the documents, but nothing else.