On Feb 7, 2022, the FreeCAD project migrated all issues from this site at tracker.freecad.org to our main GitHub repository. All new bugs must be submitted there.
This Mantis repository is in read-only mode and will be retained for reference as long as it is useful.
Thanks @mlampert and @sliptonic for assisting in tracking down the error via unit test analysis.
FreeCADGui usage has to be behind an 'if FreeCAD.GuiUp:` test
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