I think RFC 2616 should be revised.
I think RFC 2616 should make an exception for a special case where content type says it is "application/".
An example of this is "application/x-httpd-php".
Which would be treated as a download"
But if the extension says .htm, .html, .asp, .php , etc ; then I think you should check the content to see if it is a web page.
If it is; then render it.
Especially since you have incompetent web developers/ web masters out on the web.
The Browser should be more forgiving in this case.
But for FireFox the only way to get this changed is to get RFC 2616
I appreciate any comments on this.