docs: add notes for Odin v3

Documentation~/AddressableImporter.md

@@ -126,8 +126,20 @@ AddressableImporter.FolderImporter.ReimportFolders(new string[] { "Assets" });
 
 When both prefab mode (the preview scene for editing a prefab) and the autosave feature are enabled, every modification will cause the asset to be saved and trigger the importer, leads to slow response. For performance reasons, the importer will ignore the current editing asset.
 
-## ODIN Inspector Support
+## Odin Inspector Support
+
+Since v0.9.0, the importer supports [Odin inspector](https://assetstore.unity.com/packages/tools/utilities/odin-inspector-and-serializer-89041?aid=1011lJJH) (affiliates) to optimize the user experience. Odin is a paid tool to boost editor plugin development. The integration allows filter or order importer rules easier. The Odin support is optional. To enable it, just install the Odin library.
+
+Since v0.11.0, the importer only support Odin v3. Please make sure the `Scripting Define Symbols` of `Player Settings` contains `ODIN_INSPECTOR` and `ODIN_INSPECTOR_3` flags.
+
+![image](https://user-images.githubusercontent.com/125390/119212523-8700f580-baeb-11eb-8f3f-84246750152c.png)
+
+If you no longer use Odin, please remove the flags above, otherwise Unity will report a compile error:
+
+```
+error CS0246: The type or namespace name 'ISearchFilterable' could not be found (are you missing a using directive or an assembly reference?)
+```
+
+Notice that the Odin support may be moved to an additional plugin or discontinued if the importer's UX gets improved in the future.
 
-Since v0.9.0, the import supports [ODIN inspector](https://assetstore.unity.com/packages/tools/utilities/odin-inspector-and-serializer-89041?aid=1011lJJH) (affiliates) to optimize the user experience. ODIN is a paid tool to boost editor plugin development. The integration allows filter or order importer rules easier. The ODIN support is optional. To enable it, just install the ODIN library.
 
-However, the ODIN support may be discontinued if the importer's UX gets improved in the future.