Steps to reproduce:
Add a WC Structure with an Text field, Decimal field, Integer field and a Number field
Add AP portlet to a page
In Configuration, select the Web Content Article Asset Type
Select the created structure in the article sub-type
Flag the Filter by Field checkbox, click Select button, and select any field don't fill the value and click Apply
The pop-up is not closed and you can see an error message.
The pop-up is closed and you can see the selected value is null.