source/blender/blenkernel/intern/attribute_access.cc

@@ -441,9 +441,13 @@ bool BuiltinCustomDataLayerProvider::try_create(void *owner,
   if (add_custom_data_layer_from_attribute_init(
           name_, *custom_data, data_type_, element_num, initializer))
   {
+    if (initializer.type != AttributeInit::Type::Construct) {
+      /* Avoid calling update function when values are not initialized. In that case
+       * values must be set elsewhere anyway, which will cause a separate update tag. */
       if (update_on_change_ != nullptr) {
         update_on_change_(owner);
       }
+    }
     return true;
   }
   return false;