void AddBookmarkedScene()
        {
            EditorGUILayout.BeginHorizontal();
            sceneToAdd = EditorGUILayout.ObjectField(sceneToAdd, typeof(SceneAsset), false) as SceneAsset;
            if (GUILayout.Button("Add", EditorStyles.miniButtonRight) && sceneToAdd != null && !BookmarkedScenes.Contains(sceneToAdd))
            {
                BookmarkedScenes.Add(sceneToAdd);
                Preferences.Save();
                sceneToAdd = null;
            }

            EditorGUILayout.EndHorizontal();
        }
 void RemoveBookmarkedScene(SceneAsset scene)
 {
     BookmarkedScenes.Remove(scene);
     Preferences.Save();
     Repaint();
 }