my $dom = Mojo::DOM->new;

$dom->parse(<<EOF);
<?xml version="1.0"?>
<!-- This is a Test! -->
<!DOCTYPE root [
  <!ELEMENT root (#PCDATA)>
  <!ATTLIST root att CDATA #REQUIRED>
]>
<root att="test">
  <![CDATA[<greeting>Hello, world!</greeting>]]>
</root>
EOF
is substr($dom->to_xml,-7,7), '</root>', 'right final element';