FeatureForm does not validate properly when using nullable numeric field with codded value domain

[MKY]

I use feature form to edit attributes in JS api 4.16. One of the fields is a nullable numeric field (Year) with codded value domains. 

When I try to populate the field from the dropdown and select empty value I get an error (see below).

Also, once the field is populated with a numeric value and I try to change it to null value, I do not see a null value in the dropdown.

The feature Service - Layer: TestPoint (ID: 0) 

Here is a working example on code pen : https://codepen.io/markoskifle/pen/PoNzmpm 

[MKY]

This issue applies to 4.16