What makes you think www.ubuntu.com is not prerendered html5?
http://design.canonical.com/2014/03/making-ubuntu-com-respon...
goes 404, I assume there's a handler that built the page on the fly.
No?
RewriteEngine On
RewriteCond %{REQUEST_URI} !^.*\.html$
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ %{REQUEST_FILENAME}.html
Which means you can access:Surely there should be something there...