GameObject fields correctly sync, but when GameObject changes, it does not trigger the OnValueSynced attribute as with other types such as int… ie: OnValueSyncedSampleMethod(GameObject old, GameObject new)
Value sync callbacks are currently only supported for value types. That means the following types are not supported: byte[ ], CoherenceSync, GameObject, Transform and RectTransform.
Sorry! But in any case, something we need to look into and make it happen! Hence the currently in that text.