Unknown exception while reading attribute 'Surface' of object 'TopoShape'

[Andy1978]

FreeCAD_1.1.1-Linux-x86_64-py311.AppImage on Debian GNU/Linux but also tested on Windows.
Optics Workbench 1.3.2

When using Part Design -> Two Sketches -> inwards thickness all is fine but if outward thickness is selected I get

Unknown exception while reading attribute 'Surface' of object 'TopoShape'
17:50:27 Traceback (most recent call last):
17:50:27 File "/home/andy/.local/share/FreeCAD/v1-1/Mod/OpticsWorkbench/./Ray.py", line 425, in makeInitialRay
tracedLines = self.traceRay(fp, (firstLine, energy, 0.0))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
17:50:27 File "/home/andy/.local/share/FreeCAD/v1-1/Mod/OpticsWorkbench/./Ray.py", line 681, in traceRay
isec_struct = self.getIntersections(fp, line)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
17:50:27 File "/home/andy/.local/share/FreeCAD/v1-1/Mod/OpticsWorkbench/./Ray.py", line 490, in getIntersections
isec = optobj_line.Curve.intersect(face.Surface)
^^^^^^^^^^^^
17:50:27 Base.FreeCADError: Unknown exception while reading attribute 'Surface' of object 'TopoShape'

(the images shows the test on windows)

I would like to upload the .FCStd files but github won't let me.

thickness_outwards.pdf

I've renamed thickness_outwards.FCStd to thickness_outwards.pdf

[chbergmann]

I debugged this issue.
We are getting the error: Base.FreeCADError: Unknown exception while reading attribute 'Surface' of object 'TopoShape'
The Optics workbench cannot read the Surface attribute of an
The OffsetSurface does have a Surface attribute.
This is a bug inside the Thickness feature. I cannot fix this in the Optics workbench

[Andy1978]

Thank you for your reply. Have you filed an upstream bugreport or should I do?

[chbergmann]

I have not. Feel free to do ii. Thanks.