Here is my rule:
RewriteRule ^(.*)\.html$ /$1.php
This works for "virtual" .html urls which have a matching physical .php file on the server.
However when I type in a url for an actual .html file, I cannot access it, because of course the rule above is telling the server to look for a physical .php file.
So how can the rule be modified to apply to URLs only if there is a physical .php file, else load the .html file as is.