Markdown not showing up on Jekyll site?

As described in the kramdown syntax , you must enable parsing of labels in html block elements. There are two ways to do this:

Globally : in _config.yml add:

kramdown:  
  parse_block_html: true

      

        
        
        
      

    

or at the beginning of your markdown document (not in the yaml header):

{::options parse_block_html="true" /}

      

        
        
        
      

    

Locally : Add markdown="1"

to your html block to get markdown inside the highlighted block.

So, in your case, this will read:

<article markdown="1" class="post-content">
<!-- Contents of md files here in plain text-->
</article>