📝 Update release notes

docs/release-notes.md

@@ -1,5 +1,11 @@
 ## Next release
 
+* Add OAuth2 redirect page for Swagger UI. This allows having delegated authentication in the Swagger UI docs. For this to work, you need to add `{your_origin}/docs/oauth2-redirect` to the allowed callbacks in your OAuth2 provider (in Auth0, Facebook, Google, etc).
+    * For example, during development, it could be `http://localhost:8000/docs/oauth2-redirect`.
+    * Have in mind that this callback URL is independent of whichever one is used by your frontend. You might also have another callback at `https://yourdomain.com/login/callback`.
+    * This is only to allow delegated authentication in the API docs with Swagger UI.
+    * PR [#198](https://github.com/tiangolo/fastapi/pull/198) by [@steinitzu](https://github.com/steinitzu).
+
 * Make Swagger UI and ReDoc route handlers (*path operations*) be `async` functions instead of lambdas to improve performance. PR [#241](https://github.com/tiangolo/fastapi/pull/241) by [@Trim21](https://github.com/Trim21).
 
 * Make Swagger UI and ReDoc URLs parameterizable, allowing to host and serve local versions of them and have offline docs. PR [#112](https://github.com/tiangolo/fastapi/pull/112) by [@euri10](https://github.com/euri10).