title: Wicket: ListView not updated when using multiple browser windows in simple CRUD
body: <p>Ok, here is my controller using Wicket 1.5M2:</p>
  
  <pre><code>public class Users extends WebPage {
  
  private static final List&lt;User&gt; users = Collections.synchronizedList(new ArrayList&lt;User&gt;());
  
  public Users() {
  
      final UserForm userForm = new UserForm("userForm");
      add(userForm);
  
      add(new ListView&lt;User&gt;("users", users) {
  
          @Override
          protected void populateItem(ListItem&lt;User&gt; item) {
              final User user = item.getModelObject();
  
              item.add(new Label("name", user.getName()));
              item.add(DateLabel.forDatePattern("dateOfBirth", new Model(user.getDateOfBirth()), "dd.MM.yyyy"));
              item.add(new Label("email", user.getEmail()));
  
              item.add(new Link("editLink") {
  
                  @Override
                  public void onClick() {
                      userForm.setModelObject(user);
                  }
  
              });
  
              item.add(new Link("removeLink") {
  
                  @Override
                  public void onClick() {
                      users.remove(user);
                  }
  
              });
          }
  
      });
  
      setVersioned(false);
  }
  
  private class UserForm extends Form&lt;User&gt; {
  
      public UserForm(String id) {
          super(id, new CompoundPropertyModel&lt;User&gt;(new User()));
  
          add(new TextField&lt;String&gt;("name"));
          add(DateTextField.forDatePattern("dateOfBirth", "dd.MM.yyyy"));
          add(new TextField&lt;String&gt;("email"));
      }
  
      @Override
      protected void onSubmit() {
          User user = getModelObject();
          users.remove(user);
          users.add(user);
          setModelObject(new User());
      }
  }
  }
  </code></pre>
  
  <p>It works when I use only one browser window at a time for CRUD operations. If I use two windows, the list of users does not update, unless I input the base address again to the address field to reload the page.</p>
  
  <p>CLARIFICATION: Using different browsers simultaneously in same computer works good. Only when using multiple windows in same browser it does not work.</p>
  
  <ul>
  <li><p>What is happening behind the scenes?</p></li>
  <li><p>I set setVersioned(false) for the whole page, why is it that my address bar shows addresses like: <a href="http://localhost:8080/wicket/bookmarkable/package.name.Users?2" rel="nofollow">http://localhost:8080/wicket/bookmarkable/package.name.Users?2</a>
  Isn't that number 2 the version of the page?</p></li>
  <li><p>Most importantly what do I need to do to make this behave like a desktop GUI app, so one browser window == one instance of the app.</p></li>
  </ul>