Non-planar sweep sketches

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Hello,

after discovering the fantastic work of @ppemawm with version 0.20 of FreeCAD and Assembly 4 (https://forum.freecadweb.org/viewtopic.php?f=24&t=67784&sid=8a34d2ec409be9f1555fcf210a7f6ce6 ), I try to resume the project with FreeCAD LinkBranch to use another approach and try to stay in PartDesign, then do the assemblies with Assembly 3. Considering the amount of work involved, the project might be long, if I can manage it!

For now I'm working on the MotorbikeFrame and as expected, thanks to the new tools built into PartDesign in LinkBranch, I didn't need to leave PartDesign to create non-planar sweep sketches.
Apart from some display issues that occur after a while (see attached image), I noticed that after a 3D sketch sweep, the result is not automatically merged with the previous step, although the Refine property is True.
Is there something I missed?

On the other hand, I would suggest that the construction of the 3D sketch can be integrated in the Pipe stage, like the sketch of the section.

Thank you so much.