JSFiddle - React, Tailwind, and code Playground

by John Doe

HTML

<div id="main">This is...... I don't know. Something</div><br />

JavaScript

var elem = document.getElementById('main');

setTimeout(function() {
    var e = document.createElement('div');
    elem.appendChild(e.appendChild(document.createTextNode('Newly created Div')))
}, 5000);

elem.addEventListener("DOMNodeInserted", function (ev) {
  alert('New element detected')
}, false);