Document Ready (edit)

https://developer.mozilla.org/en-US/docs/Web/Events/DOMContentLoaded

https://codepen.io/LukeAskew/pen/LnJsE

https://ehkoo.com/bai-viet/co-the-ban-khong-can-jquery

<script>
//Way 1:
  document.addEventListener("DOMContentLoaded", function(event) { 
    console.log("DOM fully loaded and parsed"); 
  });

//Way 2:
  function doSomething() {
    console.info("DOM loaded");
  }
  if (document.readyState === "loading") {  // Loading hasn't finished yet
    document.addEventListener("DOMContentLoaded", doSomething);
  } else {  // 'DOMContentLoaded' has already fired
    doSomething();
  }

//Way 3:
  GLOBALS = {};
  GLOBALS.myFunc = function (e) {
    // ...
  }
  document.addEventListener('DOMContentLoaded', GLOBALS.myFunc, false);
</script>