JSFiddle - React, Tailwind, and code Playground

HTML

<div id="div1">
    <!-- <p>This is a comment.</p> -->
</div>

JavaScript

function uncommentNode(node) {
	var nodestr = node.innerHTML;
	var noderevealHTML =  nodestr.replace(/<!--/ig, '').replace(/-->/ig, '');
	node.innerHTML = noderevealHTML;
}
var elem = document.getElementById('div1');
uncommentNode(elem);