Literally guessing here, but does XDR support backwards compatibility with updated definitions? Protobufs let you add a property to a definition as long as it's

Literally guessing here, but does XDR support backwards compatibility with updated definitions? Protobufs let you add a property to a definition as long as it's at the end of the object definition, yet objects encoded in the old definition can still be decoded with it and vice versa.