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