Undo does not working after Breaking Prefab instance from Script

I breaking prefab instances pretty often. So i want to have a shortcut for it and wrote a simple script. It works fine, but undo does not work, even with Undo.RecordUndo(obj, "history name"). How can i improve this script, to make undo work?

Here is the script:

Code (CSharp):

1. [MenuItem("MyGameTools/Unconnect prefab (break) %u")]
2. static void UnconnectPrefab() {
3.     string msg = "";
4.     if (Selection.gameObjects.Any()) {
5.         foreach (var go in Selection.gameObjects) {
6.             Undo.RecordObject(go, "disconnect prefab " + go);
7.             PrefabUtility.DisconnectPrefabInstance(go);
8.             EditorUtility.SetDirty(go);
9.             msg += go.name + " – disconnect prefab\n";
10.         }
11.     } else {
12.         msg = "No objects seleted to disconnect prefab";
13.     }
14.     Debug.Log(msg);
15. }

Alternativly any method to map editor's "Break Prefab Instance" to hotkey would work for me too, because undo works there out of the box.

 

Oh, i think i found solution, calling this before register undo works:

Code (CSharp):

1. Undo.RegisterCompleteObjectUndo(go, "disconnect prefab " + go);