Forgot to add include of new JS file

src/popup.html

@@ -185,7 +185,7 @@
           </fieldset>
           <fieldset>
             <legend>HTTP Proxy (Optional)</legend>
-            <input type="text" name="container-proxy" id="edit-container-panel-proxy" maxlength="15" placeholder="IP:PORT or USER:PASS@IP:PORT"/>         
+            <input type="text" name="container-proxy" id="edit-container-panel-proxy" maxlength="15" placeholder="IP:PORT or USER:PASS@IP:PORT"/>
           </fieldset>
         </form>
         <div id="edit-sites-assigned" class="scrollable" hidden>
@@ -217,6 +217,7 @@
   </div>
 
   <script src="js/utils.js"></script>
+  <script src="js/proxified-containers.js"></script>
   <script src="js/popup.js"></script>
 </body>
 </html>