Unity Substance Editor App Error

I'm getting the following error in Unity 2021.1.14f1
It looks like it relates to the Unity Substance Editor App.

It was working okay in Unity 2021.1.12f1

> Do not use ReadObjectThreaded on scene objects!
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Substance.Editor.EntryPoint:StateChange (UnityEditor.PlayModeStateChange)
UnityEditor.EditorApplication:Internal_PlayModeStateChanged (UnityEditor.PlayModeStateChange)


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Plugin Info:
Release Version: 2.6.0b
Importer Version: 29

Build Info:
Substance Engine Version: 65545.7.2.9 639766099
Build Number: 118
Commit Hash: 2b1f4be3a8d28
Plugin Commit: bb5b08a59db3d1ee3e4da1f31e6bcfdfc0cde11e
Plugin Build: 53