Upgrade to 6.12.0+ with AjaxFormComponentUpdatingBehavior reloads the page

[Behrooz Nobakht]

Hi,

I just upgraded an Apache Wicket application from 6.12.0 to 6.13.0 with a
page including form with the following component:

```
textfield.add(new AjaxFormComponentUpdatingBehavior("onchange") {
 private static final long serialVersionUID = 1L;
 @Override
 protected void onUpdate(AjaxRequestTarget target) {
target.add(button);
 String validationMessage = validateModel(model);
if (validationMessage != null) {
addErrorMessage(target, feedback, validationMessage);
 button.setEnabled(false);
return;
}

button.setEnabled(true);
}
});
```

With 6.13.0, when I write something in the textfield and then press a tab
(go to next field), the page automatically gets reloaded. Is this a known
issue? What am I missing?

Thanks in advance,
Behrooz



-- 
-- Behrooz Nobakht