JSFiddle - React, Tailwind, and code Playground

by Rykus0

HTML

<h1>Heading</h1>
<h2>Heading</h2>
<h3>Heading</h3>
<h4>Heading</h4>
<h5>Heading</h5>
<h6>Heading</h6>

<h1>Heading</h1>
<h2>Heading</h2>
<h3>Heading</h3>
<h4>Heading</h4>

<div>
    <h1>Heading</h1>
<h2>Heading</h2>
<h3>Heading</h3>
<h4>Heading</h4>
<h5>Heading</h5>
<h6>Heading</h6>
</div>

JavaScript

$('h2').each(function(){
    $(this).nextUntil('h4+*').addBack().wrapAll('<fieldset>');
});