Complete the versioning and writing changes from these commits: -f9b627d29c-f2bcd73bd2-c5ba8bd7c24.5 has the forward compatibility handling to support reading files written by 5.0. This removes the conversion when writing files and removes the lookup of ".uv_seam" as a fallback for "uv_seam". Pull Request: https://projects.blender.org/blender/blender/pulls/139841