Mahatma Gandhi, Steve Jobs, Mother Teresa, Aristotle, and May West. What do all of these names have in common? Well, according to [1] they have all used and enjoyed Markdown.
The example site is "Access denied".
Looking at the other problems posted here, it's very clear that I won't ever touch it.
Error code: SEC_ERROR_UNKNOWN_CRITICAL_EXTENSION
Seems to be fixed now.