Steps to reproduce :

- open the Asset Store
- import the Shader Forge package https://assetstore.unity.com/packages/tools/user-tools/visual-scripting/shader-forge-14147
- try and open the Shader Forge window and notice the errors

NullReferenceException: Object reference not set to an instance of an object
ShaderForge.SF_PreviewWindow.SetupPreview ()
ShaderForge.SF_PreviewWindow..ctor (ShaderForge.SF_Editor editor)
ShaderForge.SF_Editor.InitializeInstance (UnityEngine.Shader initShader)
ShaderForge.SF_Editor.Init (UnityEngine.Shader initShader)
ShaderForge.SF_Editor.InitEmpty ()

NullReferenceException: Object reference not set to an instance of an object
ShaderForge.SF_Editor.OnDestroy ()
UnityEditor.EditorWindow:Close()
ShaderForge.SF_Editor:Update()
UnityEditor.EditorApplication:Internal_CallUpdateFunctions()