CoreData NSValueTransformer cannot be found after adding new Core Data version

Question

I have a note attribute in Core Data, which is Transformable.

I am using NSAttributedStringTransformer as follows:

@objc(NSAttributedStringTransformer)
class NSAttributedStringTransformer: NSSecureUnarchiveFromDataTransformer {
        override class var allowedTopLevelClasses: [AnyClass] {
                return super.allowedTopLevelClasses + [NSAttributedString.self]
        }
}

The code works as expected. When I add new Core Data version. I get the following no NSValueTransformer with class name 'NSAttributedStringTransformer' was found for attribute 'note' on entity 'NotesEntity'. I haven't made any other changes. Do I need to change the NSAttributedStringTransformer in order to work with Core Data versions?