Solvespace version: Recent master - e74c2ea

When I link the following old file:
extrude_test.zip

there is a triangulation problem with the spline curve. It's as if a different curve is used to cut the top and bottom surfaces of the extrusion, although the end points look correct.

If this same file is opened with this version of solvespace there is no problem. If it is resaved it can be correctly linked into a new sketch. Regeneration seems to fix the problem.

I found this while linking a very old file to investigate #1669 It seems relevant since linked sketches create "linked" sketch entities. I have no idea why it's the spline shaped hole that is broken.