Returns a dictionary containing the keys and old values of persistent properties that have changed since the last posting of NSManagedObjectContextObjectsDidChange.
Mac Catalyst 13.0+
A dictionary whose keys are the names of persistent properties that have changed since the last posting of NSManagedObjectContextObjectsDidChange, and whose values are the old value of the persistent 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.