What happened?
Copy and Paste properties doesn't work if you put SerializeReference objects inside regular SerializeField objects.
Per example:
Then when you try to copy TestData in inspector you only get Copy option that can't copy anything related to SerializeReference:
Moreover if in this setup you try to copy just filter:

Then when you try to paste that filter to analogous testData2 you get an exception
Similar problem with SubclassSelector collections. Is this intended or it's a bug? And if it's not bug then can you please add support for such type of Copy-Paste
Package Version
1.6.1
Unity Version
6000.3.7f1