Show HN: Markdown Crash Test: benchmark Markdown everywhere

## Why that?

I'm using Markdown for 5 years, to take notes and edit a bunch of Hugo websites.

Along the way, I've tried countless Markdown editors, and tested dozens of Jamstack themes.

Checking the support of each Markdown feature became part of the routine, so I end-up collecting this checklist.

I hope this can help someone out there!