code: function (eventType, params) {
      params = params || {
          bubbles: false,
          cancelable: false,
          ctrlKey: false,
          altKey: false,
          shiftKey: false,
          metaKey: false
        };
      var mouseEvent = document.createEvent('MouseEvent');
      mouseEvent.initMouseEvent(eventType, params.bubbles, params.cancelable, window, 0, 0, 0, 0, 0, params.ctrlKey, params.altKey, params.shiftKey, params.metaKey, 0, null);
  
      return mouseEvent;
    }
docs: Polyfills DOM4 MouseEvent