Expected behavior

Vertical stepper component working shown here (MDB Stepper) on IE 11.

Actual behavior

I've updated to 4.9.0 and ran all of the GULP build scripts, yet I cannot get my stepper page to work in IE 11. However, on the demo page, it is working fine?

Resources (screenshots, code snippets etc.)

SCRIPT1002: Syntax errormdb.min.js (1,412827)jQuery.Deferred exception: Object doesn't support property or method 'mdbStepper' TypeError: Object doesn't support property or method 'mdbStepper' at Anonymous function (http://localhost:3000/js/ready.js:3:5) at e (http://localhost:3000/js/jquery-3.4.1.min.js:2:29445) at Anonymous function (http://localhost:3000/js/jquery-3.4.1.min.js:2:29755) undefinedSCRIPT438: Object doesn't support property or method 'mdbStepper'jquery-3.4.1.min.js (2,31118)

/* !
 * jQuery Validation Plugin v1.17.0
 *
 * https://jqueryvalidation.org/
 *
 * Copyright (c) 2017 Jörn Zaefferer
 * Released under the MIT license
 */
(function (factory) {
  if (typeof define === 'function' && define.amd) {
    define(['jquery'], factory);
  } else if (typeof module === 'object' && module.exports) {
    module.exports = factory(require('jquery'));
  } else {
    factory(jQuery);
  }
}(($) => {

It does not like the last line with the =>

Also, this is how I'm calling it

$(document).ready(function () {
    // Init the stepper
    $('.stepper').mdbStepper({
        autoFormCreation: false
    });
})