xml-compatible">XML-compatible</dfn>
      attribute names are those that match the
      <a href="https://www.w3.org/TR/REC-xml/#NT-Name"><code>Name</code></a> production defined in
      the XML specification <a href="references.html#refsXML" id="refsXML_xref6">[XML]</a>
      and that contain no
      "<code title="U+003A COLON">:</code>"
      characters, and whose first three characters are not a
      <a href="terminology.html#case-insensitive" id="case-insensitive_xref12">case-insensitive match</a>
 