Setting missing fields always dirties the form

[vincaslt]

I did not provide a particular field in defaultValues but I registered that field in the form. The form is always dirty (form.formState.isDirty=true), even though there are no dirty fields (form.formState.dirtyFields={}). This happens regardless of shouldUnregister being true of false. Curiously, I can't reset the form then, and that fields value is always set to undefined.