These tests have come about due to the number of people using XHTML as if it is HTML. The tests highlight some issues that developers should beware of if they are using XHTML. For more details, see it's all in the MIME. See Specifying a MIME Type for more information about XHTML and MIME types.
The following tests are purely to examine the difference between serving XHTML documents with a MIME type of
text/html. Some of the documents do not conform to the XHTML specification. Those that fall into this category are marked as invalid.
XHTML Mime Type Tests
- Unencoded ampersand (invalid)
- Delivered as application/xhtml+xml regardless of the capabilities of the browser
- Styling the body element
- Table without a tbody element
- Using document.write
- Using innerHTML
- CSS elements specified in uppercase
- Character Encoding Test
- Mixing XHTML with MathML
- Table image rows
- Using xml:base
- Using XPath