JSFiddle - React, Tailwind, and code Playground

by wrxsti85

HTML

<p id="observable" style="color: red">Lorem ipsum</p>

JavaScript

var MutationObserver = window.WebKitMutationObserver;

var target = document.querySelector('#observable');

var observer = new MutationObserver(function(mutations) {
  mutations.forEach(function(mutation) {
    console.log('old', mutation.oldValue);
    console.log('new', mutation.target.style.cssText);
  });    
});
  
var config = { attributes: true, childList: true, characterData: true, attributeOldValue: true }

observer.observe(target, config);

target.addEventListener('click', function(ev) {
    observable.style.color = 'green';
    return false;
}, false);