December 08, 2004
'application/xhtml+xml'
... if you are using the usual HTML features (no MathML) and are serving your content as text/html to other browsers, there is no need to serve application/xhtml+xml to Mozilla. In fact, doing so would deprive the Mozilla users of incremental display, because incremental loading of XML documents has not been implemented yet. Serving valid HTML 4.01 as text/html ensures the widest browser and search engine support.