Disallow Modifications In Attribute

DisallowModificationsIn disables / grays out members, preventing modifications from being made and enables validation, providing error messages in case a modification was made prior to introducing the attribute. 

[DisallowModificationsIn(PrefabKind.PrefabInstanceAndNonPrefabInstance)]
public string PrefabInstanceAndNonPrefabInstance = "Prefab Instances, as well as non-prefab instances";

[DisallowModificationsIn(PrefabKind.InstanceInScene)]
public string InstanceInScene = "Instances of prefabs in scenes";

[DisallowModificationsIn(PrefabKind.InstanceInPrefab)]
public string InstanceInPrefab = "Instances of prefabs nested inside other prefabs";

[DisallowModificationsIn(PrefabKind.Variant)]
public string Variant = "Prefab variant assets";

[DisallowModificationsIn(PrefabKind.NonPrefabInstance)]
public string NonPrefabInstance = "Non-prefab component or gameobject instances in scenes";

[DisallowModificationsIn(PrefabKind.PrefabInstance)]
public string PrefabInstance = "Instances of regular prefabs, and prefab variants in scenes or nested in other prefabs";