Document all markdown features.

[RocketRide9]

Currently markdown documentation at https://join-lemmy.org/docs/users/02-media.html lacks information about tables and footnotes. At least that's what I could find. Including full documentation about extended markdown features is very useful for developers of client apps, because lack of such support in their apps can hurt their reputation. And it's very unfortunate, when lack of support is only because developer doesn't know about such features.

[dessalines]

I'm not sure markdown can do a table within a table, but you could add footnotes to that table if you like.

[RocketRide9]

I'm not sure markdown can do a table within a table, but you could add footnotes to that table if you like.

I assume tables are from gfm and spec says that cells are inlines and table itself is a leaf: https://github.github.com/gfm/.

Markdown-it-footnote references pandoc in their readme and pandoc doesn't seem to be documented as well as commonmark: https://pandoc.org/MANUAL.html#footnotes. I think footnote coment is a container and reference is inline.

[Nutomic]

Feel free to make a pull request. The file is here:

https://github.com/LemmyNet/lemmy-docs/blob/main/src/users/02-media.md

[dessalines]

I also don't think we need an comprehensive markdown guide, that's done better elsewhere, and we even link to one. Just the basics, and the lemmy-specific additions.