With the previous fix to the node, 8a11f0f3a2, the new edge
indices are built with the changed corner vertices from a previous step
in the algorithm. That doesn't work for loose edges though, since they
aren't used by any face corners. The best solution I could come up with
was adding a second loop over the split vertices that adjusts the vertex
indices of loose edges. This can be skipped when there are none.
Pull Request: https://projects.blender.org/blender/blender/pulls/109262
b226c115e2