[Unity] NullReferenceException

NullReferenceException: Object reference not set to an instance of an object UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition) (at <780782bc035845f9909cebbd4c983ae3>:0) UnityEditor.DockArea.DrawView (UnityEngine.Rect dockAreaRect) (at <780782bc035845f9909cebbd4c983ae3>:0) UnityEditor.DockArea.OldOnGUI () (at <780782bc035845f9909cebbd4c983ae3>:0) UnityEngine.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 parentTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout, UnityEngine.Rect layoutSize, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <f23cc42ed8af4b73afc7c74ab921aa08>:0) UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr, Boolean&)

 

이 오류가 생기는 원인은 모르지만 unity 프로젝트와 unity hub를 모두 껐다가 재실행하면 사라지는 오류다.