Merge branch 'blender-v2.83-release'

release/scripts/startup/bl_ui/space_topbar.py

@@ -309,16 +309,18 @@ class TOPBAR_MT_file_new(Menu):
 
         template_paths = bpy.utils.app_template_paths()
 
-        # expand template paths
-        app_templates = []
+        # Expand template paths.
+
+        # Use a set to avoid duplicate user/system templates.
+        # This is a corner case, but users managed to do it! T76849.
+        app_templates = set()
         for path in template_paths:
             for d in os.listdir(path):
                 if d.startswith(("__", ".")):
                     continue
                 template = os.path.join(path, d)
                 if os.path.isdir(template):
-                    # template_paths_expand.append(template)
-                    app_templates.append(d)
+                    app_templates.add(d)
 
         return sorted(app_templates)
 

source/blender/blenkernel/intern/multires_reshape.c

@@ -197,7 +197,16 @@ void multiresModifier_subdivide_to_level(struct Object *object,
   if (!has_mdisps) {
     CustomData_add_layer(&coarse_mesh->ldata, CD_MDISPS, CD_CALLOC, NULL, coarse_mesh->totloop);
   }
-  if (!has_mdisps || top_level == 1) {
+
+  /* NOTE: Subdivision happens from the top level of the existing multires modifier. If it is set
+   * to 0 and there is mdisps layer it would mean that the modifier went out of sync with the data.
+   * This happens when, for example, linking modifiers from one object to another.
+   *
+   * In such cases simply ensure grids to be the proper level.
+   *
+   * If something smarter is needed it is up to the operators which does data synchronization, so
+   * that the mdisps layer is also synchronized. */
+  if (!has_mdisps || top_level == 1 || mmd->totlvl == 0) {
     multires_reshape_ensure_grids(coarse_mesh, top_level);
     if (ELEM(mode, MULTIRES_SUBDIVIDE_LINEAR, MULTIRES_SUBDIVIDE_SIMPLE)) {
       multires_subdivide_create_tangent_displacement_linear_grids(object, mmd);