I'm using markdown from the repos on Ubuntu 19.10. This seems to be a quite old version:
>markdown -v
This is Markdown, version 1.0.1.
Copyright 2004 John Gruber
http://daringfireball.net/projects/markdown/
It doesn't support useful features such as "fenced" code blocks (line are concatenated as if if only kept the last of the opening backticks and the first of the closing backticks).
When I look for a markdown man page on the web there is obviously a more recent (2008) and more complete version (many more options than in my local man page). Where can I find it? Is its source available somewhere? Searching for markdown on the web is near impossible since you get thousands of hits for markdown syntax cheatsheets.