As I was griping above, you usually can't just view a Markdown file with formatting applied at all. I think MAYBE Notepad has been updated just recently to render it, but otherwise... you're looking at plain text with a bunch of formatting characters in it. Why? It's baffling. Where are the simple Markdown READERS?
It really would be nice to have a convenient renderer for it though. It's genuinely surprising something like firefox doesn't have a markdown reader builtin already.