JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
  <div>1</div>
  <div>2</div>
  <div>3</div>
  <div>4</div>
</div>

JavaScript

var frag = document.createDocumentFragment(),
		div = document.createElement('div'),
    html = document.getElementById('container').innerHTML;
      
frag.appendChild(div);
frag.children[0].innerHTML = html;	

document.getElementById('container').innerHTML = frag.children[0].innerHTML;