="syntax-self-closing">marked as self-closing</dfn>.</li>
     <li>SVG and MathML elements
     <a href="terminology.html#must-requirement" id="must-requirement_xref54">must</a>
     either have a
     <a href="syntax.html#syntax-start-tags" id="syntax-start-tags_xref6">start tag</a>
     and an
     <a href="syntax.html#syntax-end-tags" id="syntax-end-tags_xref7">end tag</a>,
     or a start tag that is
     <a href="syntax.html#syntax-self-closing" id="syntax-self-closing_xref1">marked as self-closing</a>