add arguments to calculate normals when converting to bmesh: BM_mesh_bm_from_me, DM_to_bmesh This gives some speedup to undo (which didnt need to re-calculate vertex normals), and array modifier which doesnt need to calculate face normals at all
add arguments to calculate normals when converting to bmesh: BM_mesh_bm_from_me, DM_to_bmesh This gives some speedup to undo (which didnt need to re-calculate vertex normals), and array modifier which doesnt need to calculate face normals at all