JSFiddle - React, Tailwind, and code Playground

HTML

<div id="huita">Huita</div>
<button id="huitaChanger">Change</button>

JavaScript

var huita = document.getElementById("huita");
var changer = document.getElementById("huitaChanger");
changer.onclick = function() {changeHuita(huita)};

function changeHuita(huita) {
    huita.innerHTML = "Ne huita";
}

var observer = new MutationObserver(function(mutations) {
  mutations.forEach(function(mutation) {
    if(mutation.type == "childList") {
        var val = mutation.removedNodes[0].nodeValue
        alert("THEY CHANGED MY HUITA OMG!!1 It's value was: " + val);
    }
  });    
});

var config = {attributes: true, childList: true, characterData: true};
 
observer.observe(huita, config);