* ⬆ Upgrade version pin accepted for Flake8, for internal code, to `flake8 >=3.8.3,<6.0.0`. PR [#4097](https://github.com/tiangolo/fastapi/pull/4097) by [@jamescurtin](https://github.com/jamescurtin).
* 🐛 Fix support for extending `openapi_extras` with parameter lists. PR [#4267](https://github.com/tiangolo/fastapi/pull/4267) by [@orilevari](https://github.com/orilevari).
* ✨ Add support for `FrozenSet` in parameters (e.g. query). PR [#2938](https://github.com/tiangolo/fastapi/pull/2938) by [@juntatalor](https://github.com/juntatalor).
* ✨ Allow custom middlewares to raise `HTTPException`s and propagate them. PR [#2036](https://github.com/tiangolo/fastapi/pull/2036) by [@ghandic](https://github.com/ghandic).