JAVASCRIPT

find overflow element

/* Add code to website or in element inspect to simply see overflowing elements*/
* {
  outline: 1px solid #f00 !important;
}

javascript to help find overflow elements

var docWidth = document.documentElement.offsetWidth;

[].forEach.call(
  document.querySelectorAll('*'),
  function(el) {
    if (el.offsetWidth > docWidth) {
      console.log(el);
    }
  }
);