But with that MIME type it wasn't XHTML at all. It was being parsed as HTML which was possible only because of big similarity between those two formats. All you

But with that MIME type it wasn't XHTML at all. It was being parsed as HTML which was possible only because of big similarity between those two formats. All you need to ensure the behavior you want is to disable HTML parsing (which is pretty much ensures being liberal in what the parser accepts already in its specification).