Markdown pattern extraction issue

[cornae]

I have issue with extracting the second chapter of the documentation of [grid[(http://patternslib.com/demo/grid/index.html).

The markdown file says

## Documentation
### The grid

**Create powerful multi-d…

What it plots though is only the header 'Documentation' and not the rest. When I put a line of text underneath ## Documentation, then that line will be displayed. But still not the ### The grid and on.