I am basically doing this tutorial
But using take a snapshot gives this error.
Unity version 2020.2
NullReferenceException: SerializedObject of SerializedProperty has been Disposed.
UnityEditor.SerializedProperty.Verify (UnityEditor.SerializedProperty+VerifyFlags verifyFlags) (at <8c48e4bc2ff34638b69095cbb65e2e27>:0)
UnityEditor.SerializedProperty.set_objectReferenceValue (UnityEngine.Object value) (at <8c48e4bc2ff34638b69095cbb65e2e27>:0)
UnityEditor.SceneTemplate.SceneTemplateAssetInspectorWindow.TakeSnapshotFromCamera (UnityEditor.SceneTemplate.SceneTemplateAssetInspectorWindow+SnapshotTargetInfo targetInfo, UnityEditor.SerializedProperty thumbnailProperty) (at <bee1ef464c144f93b7fc3b8867e36516>:0)
UnityEditor.SceneTemplate.SceneTemplateAssetInspectorWindow+<>c__DisplayClass53_0.<MakeThumbnailField>b__4 () (at <bee1ef464c144f93b7fc3b8867e36516>:0)
UnityEngine.UIElements.Clickable.Invoke (UnityEngine.UIElements.EventBase evt) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.Clickable.ProcessUpEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.Vector2 localPosition, System.Int32 pointerId) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.Clickable.OnMouseUp (UnityEngine.UIElements.MouseUpEvent evt) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventCallbackFunctor`1[TEventType].Invoke (UnityEngine.UIElements.EventBase evt) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventCallbackRegistry.InvokeCallbacks (UnityEngine.UIElements.EventBase evt) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.CallbackEventHandler.HandleEvent (UnityEngine.UIElements.EventBase evt) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.CallbackEventHandler.HandleEventAtTargetPhase (UnityEngine.UIElements.EventBase evt) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.MouseCaptureDispatchingStrategy.DispatchEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcher.ApplyDispatchingStrategies (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel, System.Boolean imguiEventIsInitiallyUsed) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcher.ProcessEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcher.ProcessEventQueue () (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcher.OpenGate () (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcherGate.Dispose () (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcher.ProcessEvent (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.EventDispatcher.Dispatch (UnityEngine.UIElements.EventBase evt, UnityEngine.UIElements.IPanel panel, UnityEngine.UIElements.DispatchMode dispatchMode) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.BaseVisualElementPanel.SendEvent (UnityEngine.UIElements.EventBase e, UnityEngine.UIElements.DispatchMode dispatchMode) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.UIElementsUtility.DoDispatch (UnityEngine.UIElements.BaseVisualElementPanel panel) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.UIElementsUtility.UnityEngine.UIElements.IUIElementsUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr, System.Boolean& eventHandled) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.UIEventRegistration.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.UIElements.UIEventRegistration+<>c.<.cctor>b__1_2 (System.Int32 i, System.IntPtr ptr) (at <0050475d167947ea9f166ad030caa84f>:0)
UnityEngine.GUIUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr, System.Boolean& result) (at <f8197c5efb504ab8a77daf7d0e9abc5e>:0)