JSFiddle - React, Tailwind, and code Playground

HTML

<script id="scriptBody1" type="text/xml">
    <?xml version="1.0" encoding="UTF-8"?>
    <someroot>
        <firsttag>
               <peacefultag></peacefultag>
        </firsttag>
        <secondtag>
            <a>asdsa</a>
        </secondtag>
    </someroot>
</script>

<script id="scriptBody2" type="text/xml">
    <?xml version="1.0" encoding="UTF-8"?>
    <someroot>
        <firsttag>
               <script></script>
        </firsttag>
        <secondtag>
            <a>asdsa</a>
        </secondtag>
    </someroot>
</script>

JavaScript

var scriptBody1 = $('script#scriptBody1').text(),
    scriptBody2 = $('script#scriptBody2').text(),
    result1 = $.parseHTML(scriptBody1, window.document, true),
    result2 = $.parseHTML(scriptBody2, window.document, true);

console.log('no script tag:');
console.log('firsttag:', $(result1).find('firsttag').length);
console.log('secondtag:', $(result1).find('secondtag').length);
console.log('with script tag');
console.log('firsttag:', $(result2).find('firsttag').length);
console.log('secondtag:', $(result2).find('secondtag').length);