Mutation observer example in JavaScript

observer-example.js

if (window.MutationObserver || window.WebKitMutationObserver) {
  var observer = new MutationObserver(function (mutations, observer) {
    // Do something after node has changed
    console.log('#div has changed')
  });

  // Configuration of the observer
  var config = {
    subtree: true,
    attributes: true
  }

  // The node to be monitored
  var target = document.querySelector('#div');

  // Start observing
  observer.observe(target, config);

  // Stop observing (optional)
  observer.disconnect();
}