Further investigating in the forum, I found this older thread from 2013: https://forum.freecadweb.org/viewtopic.php?t=4589:
Is it still the case that these features are not implemented ?bejant wrote: ↑Wed Sep 18, 2013 6:23 pm Mode
Only Skin functions, Pipe and RectoVerso are not implemented yet.
Intersection specifies how the algorithm must work in order to limit the parallels to two adjacent shapes:
False: (default value), the intersection is calculated with the parallels to the two adjacent shapes;
True: is not completely implemented and therefore is not recommended for use.
If so, my advice would be to remove them from the interface to limit the user confusion.
If we do so, then the Mode could default to shell and the Intersection checkbox could default to false and not be exposed anymore.
OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24267 (Git)
Build type: Release
Python version: 3.8.8
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
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