text: /**
   * Add global method if missing
   *
   * @author Paul Irish - https://github.com/paulirish
   */
  
  if (!window.requestAnimationFrame) {
  
      window.requestAnimationFrame = (() => {
  
          return window.requestAnimationFrame ||
              window.webkitRequestAnimationFrame ||
              window.mozRequestAnimationFrame ||
              window.oRequestAnimationFrame ||
              window.msRequestAnimationFrame ||
              (cb => {
                  window.setTimeout(cb, 1000 / 60);
              });
      })();
  }
  