[media type] without xmlns [text/html] recognized as HTML [text/xml] recognized as XML, XHTML-specific semantics were not recognized but the type selector in style sheets matched case-insensitively [application/xml] recognized as XML, XHTML-specific semantics were not recognized but the type selector in style sheets matched case-insensitively [application/xhtml+xml] 
recognized as XML, XHTML-specific semantics were not recognized but the type selector in style sheets matched case-insensitively