e element
     * found at the screen position given.
     */
    deepTargetFind: function(x, y) {
      let node = document.elementFromPoint(x, y);
      let next = node;
      // this code path is only taken when native ShadowDOM is used
      // if there is a shadowroot, it may have a node at x/y
      // if there is not a shadowroot, exit the loop
      while (next && next.shadowRoot && !window.ShadyDOM) {
        // if there is a node at x/y in the shadowroot, look deeper
        let oldNext = next;
   