When set to True, a <div> element will be added just after the weblet to display validation errors. the <div> will be hidden until a validation error occurs and will be hidden again when the error is cleared.
When a validation method has been set the error <div> will reserve some space for itself on the page even when it is hidden to avoid confusing rearrangements of the screen when the error is displayed. If you are using HTML 5 validation on the form but not on this field then you may want to set this property to False to reclaim that space.
True, False, or any valid XPath expression that returns a boolean value.