Steps to Reproduce

1. select 1st item
2. clear the value with backspace
3. click outside of the combobox or pressing Tab key

Current Result

it shows 2 messages

Expected Result

it shows 1 message

Debug Information

• onSelect still fires onChange in Combobox.service()

  			if (oldSel != null && !oldSel.equals(_selItem) && oldSel.getLabel().equals(val))
  				Events.postEvent(new InputEvent(Events.ON_CHANGE, this, val, val));
  

Workaround

• listen to onSelect