MouseEvent not working in Internet Explorer

Question

Is it me? Is it my IE? or why is this code not working on IE 11:

var clicker = new MouseEvent("click", {
  'bubbles': true,
  'cancelable': true,
  'view': window,
  'detail': 0,
  'screenX': 0,
  'screenY': 0,
  'clientX': 0,
  'clientY': 0,
  'ctrlKey': false,
  'altKey': false,
  'shiftKey': false,
  'metaKey': false,
  'button': 0,
  'relatedTarget': null
});

I get "Object doesn't support this action" on the console (F12). I had to come up with a workaround, but I just don't get why is the previous code not working (by the way, the previous code comes from here: https://msdn.microsoft.com/en-us/library/ie/dn905219(v=vs.85).aspx (Creating and firing synthetic events). Workaround:

if (typeof MouseEvent !== 'function') {
    (function (){
        var _MouseEvent = window.MouseEvent;
        window.MouseEvent = function (type, dict){
            dict = dict || {};
            var event = document.createEvent('MouseEvents');
            event.initMouseEvent(
                    type,
                    (typeof dict.bubbles == 'undefined') ? true : !!dict.bubbles,
                    (typeof dict.cancelable == 'undefined') ? false : !!dict.cancelable,
                    dict.view || window,
                    dict.detail | 0,
                    dict.screenX | 0,
                    dict.screenY | 0,
                    dict.clientX | 0,
                    dict.clientY | 0,
                    !!dict.ctrlKey,
                    !!dict.altKey,
                    !!dict.shiftKey,
                    !!dict.metaKey,
                    dict.button | 0,
                    dict.relatedTarget || null
            );
            return event;
        }
    })();
}

The deal is that I want to migrate the deprecated createEvent/initXXXXEvent to the new form (var event = new XXXXEvent(...) ) whenever possible and not rely on the deprecated methods.

Answer 1

The MSDN documentation from the link you provided indicates that the new syntax for the DOM L4 event constructor pattern:

Applies to Internet Explorer for Windows 10 Technical Preview and later.

which is a different version of IE from what you are using. So it's expected that IE11 does not support this feature

Answer 2

There is a polyfill to make it work in IE.

Except that the try catch block in that code needs to look like this:

try {
  new CustomEvent('test');
  return false; // No need to polyfill
} catch (e) {
  // Need to polyfill - fall through
}

I submitted this correction to their website.