📝 Update release notes

docs/en/docs/release-notes.md

@@ -2,6 +2,14 @@
 
 ## Latest changes
 
+* Add support for ASGI `root_path`:
+    * Use `root_path` internally for mounted applications, so that OpenAPI and the docs UI works automatically without extra configurations and parameters.
+    * Add new `root_path` parameter for `FastAPI` applications to provide it in cases where it can be set with the command line (e.g. for Uvicorn and Hypercorn, with the parameter `--root-path`).
+    * Deprecate `openapi_prefix` parameter in favor of the new `root_path` parameter.
+    * Add new/updated docs for [Sub Applications - Mounts](https://fastapi.tiangolo.com/advanced/sub-applications/), without `openapi_prefix` (as it is now handled automatically).
+    * Add new/updated docs for [Behind a Proxy](https://fastapi.tiangolo.com/advanced/behind-a-proxy/), including how to setup a local testing proxy with Traefik and using `root_path`.
+    * Update docs for [Extending OpenAPI](https://fastapi.tiangolo.com/advanced/extending-openapi/) with the new `openapi_prefix` parameter passed (internally generated from `root_path`).
+    * Original PR [#1199](https://github.com/tiangolo/fastapi/pull/1199) by [@iksteen](https://github.com/iksteen).
 * Update new issue templates and docs: [Help FastAPI - Get Help](https://fastapi.tiangolo.com/help-fastapi/). PR [#1531](https://github.com/tiangolo/fastapi/pull/1531).
 * Update GitHub action issue-manager. PR [#1520](https://github.com/tiangolo/fastapi/pull/1520).
 * Add new links: