Field doesn't appear in 'modified' attribute after calling 'form.change(<field>, <value>)'

[Lebed-kun]

form is an object of type FormApi. After I call form.change('field-a', <value>) for example, I expect to see 'field-a' in 'modified' field of 'form' object. But that doesn't happen, and only fields that have corresponding input elements (ex. if I have some <Select name="field-a" {...} /> somewhere inside <Form /> element) are tracked. Is there any way to track changes of fields that doesn't have matching by name UI elements with final-form API?