I tried to find a solution but I have no idea what produces it and how to solve it.NullReferenceException: Object reference not set to an instance of an object
UnityEditor.GameObjectInspector.ClearPreviewCache () (at C:/buildslave/unity/build/Editor/Mono/Inspector/GameObjectInspector.cs:195)
UnityEditor.GameObjectInspector.OnDisable () (at C:/buildslave/unity/build/Editor/Mono/Inspector/GameObjectInspector.cs:189)
UnityEditor.AssetDatabase:SaveAssets()
PixelCrushers.DialogueSystem.DialogueEditor.DialogueEditorWindow:OnDisable() (at Assets/Plugins/Pixel Crushers/Dialogue System/Scripts/Editor/Dialogue Editor/DialogueEditorWindowMain.cs:115)
Any help would be appreciated.