6f0620161d
Having both custom vertex normals and the "is the face sharp?" attribute on a mesh leads to some non-intuitive behaviours. Instead, make the behaviour more aligned with OBJ format description wording, which says "When vertex normals are present, they supersede smoothing groups" (https://paulbourke.net/dataformats/obj/). Pull Request: https://projects.blender.org/blender/blender/pulls/124366