Running example fails with 'TypeError: Super expression must either be null or a function'

[erezcarmel]

I was following the contributing instructions, and I got this error:

TypeError: Super expression must either be null or a function

  93 | 
  94 | function _inherits(subClass, superClass) {
  95 |   if (typeof superClass !== "function" && superClass !== null) {
> 96 |     throw new TypeError("Super expression must either be null or a function");
  97 |   }
  98 | 
  99 |   subClass.prototype = Object.create(superClass && superClass.prototype, {

(anonymous function)

 1906 | var ReactTooltip = staticMethods(_class = windowListener(_class = customEvent(_class = isCapture(_class = getEffect(_class = bodyMode(_class = trackRemoval(_class = (_temp = _class2 =
  1907 | /*#__PURE__*/
  1908 | function (_React$ReactNode) {
> 1909 |   _inherits(ReactTooltip, _React$ReactNode);
  1910 | 
  1911 |   _createClass(ReactTooltip, null, [{
  1912 |     key: "propTypes",

(anonymous function)

 2689 |   }]);
  2690 | 
  2691 |   return ReactTooltip;
> 2692 | }(React.ReactNode), _defineProperty(_class2, "defaultProps", {
  2693 |   insecure: true,
  2694 |   resizeHide: true,
  2695 |   wrapper: 'div',

What seems to be the problem?