Bad $ (jQuery) when import anonymous AMD module (Bootbox.js)


I try to import an anonymous AMD module : Bootbox.js.

I read Ember CLI User manual how to import it :

app.import('bower_components/bootbox/bootbox.js', {
    using: [
        { transformation: 'amd', as: 'bootbox' }

It’s OK. BUT, when i try to use it, i have an error: $.extend is not a function :disappointed:

$ (jQuery) is not well defined! In Bootbox.js code, I added a console.log to display $ value:

(function (root, factory) {

  "use strict";
  if (typeof define === "function" && define.amd) {
    // AMD. Register as an anonymous module.
    define(["jquery"], factory);
  } else if (typeof exports === "object") {
    // Node. Does not work with strict CommonJS, but
    // only CommonJS-like environments that support module.exports,
    // like Node.
    module.exports = factory(require("jquery"));
  } else {
    // Browser globals (root is window)
    root.bootbox = factory(root.jQuery);
}(this, function init($, undefined) {

  "use strict";


  ... code code code ...

$ is an JS object with a default property that is jQuery:

    __esModule: true,
    default: function ( selector, context ),
    __proto__: Object

BUT Bootbox.js uses $.extend in its code and not $.default.extend

Could someone help me to understand this and to configure/import this module? Thank you,