Returns a dictionary containing the keys and (old) values of persistent properties that have been changed since the last fetching or saving of the managed object.
Mac Catalyst 13.0+
A dictionary containing as keys the names of persistent properties that have changed since the receiver was last fetched or saved, and as values the new values of the properties.
This method only reports changes to properties that are defined as persistent properties of the receiver, not changes to transient properties or custom instance variables. This method does not unnecessarily fire relationship faults.