title: JQuery Easing and WebPack
body: <p>I have a button that have to hide a frameset and show the following one</p>
  
  <p>This a part of my HTML</p>
  
  <pre><code>&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"&gt;&lt;/script&gt;
  &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-easing/1.3/jquery.easing.min.js"&gt;&lt;/script&gt;
  &lt;script src="./js/scripts-bundled.js"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>This is where the easing function is called</p>
  
  <pre><code>import $ from "jquery";
  
  class FormController {
    // variables declararations and some code not useful now...
  
    buttonClicked(evt) {
  
      this.current_object.animate(
        { opacity: 0 },
        {
          step: function(now, mx) {
          //as the opacity of current_fs reduces to 0 - stored in "now"
          //1. scale current_fs down to 80%
          scale = 1 - (1 - now) * 0.2;
          //2. bring next_fs from the right(50%)
          left = now * 50 + "%";
          //3. increase opacity of next_fs to 1 as it moves in
          opacity = 1 - now;
          this.current_object.css({
            transform: "scale(" + scale + ")",
            position: "absolute"
          });
          this.next_object.css({ left: left, opacity: opacity });
        },
        duration: 800,
        complete: function() {
          this.current_object.hide();
          this.animating = false;
        },
        //this comes from the custom easing plugin
        easing: "easeInOutBack"
      }
    );
  }
  </code></pre>
  
  <p>If I run this code and I click on the button I receive this error
  <strong>Uncaught TypeError: jQuery.easing[this.easing] is not a function</strong></p>
  
  <p>I believe that, for some reason, the easing plugin is not loaded properly.</p>
  
  <p>Is there a way to require it inside the code via Webpack?</p>
  
  <p>Thanks</p>