diff --git a/actix-http/CHANGES.md b/actix-http/CHANGES.md
index 89ad54596..c8a2bbd92 100644
--- a/actix-http/CHANGES.md
+++ b/actix-http/CHANGES.md
@@ -3,10 +3,13 @@
 ## Unreleased
 
 - Minimum supported Rust version (MSRV) is now 1.88.
+- Increase default HTTP/2 flow control window sizes. [#3638]
+- Expose configuration methods to improve upload throughput. [#3638]
 - Fix truncated body ending without error when connection closed abnormally. [#3067]
 - Add config/method for `TCP_NODELAY`. [#3918]
 - Do not compress 206 Partial Content responses. [#3191]
 
+[#3638]: https://github.com/actix/actix-web/issues/3638
 [#3067]: https://github.com/actix/actix-web/pull/3067
 [#3918]: https://github.com/actix/actix-web/pull/3918
 [#3191]: https://github.com/actix/actix-web/issues/3191
diff --git a/actix-web/CHANGES.md b/actix-web/CHANGES.md
index a89060b57..4d33d6753 100644
--- a/actix-web/CHANGES.md
+++ b/actix-web/CHANGES.md
@@ -3,6 +3,8 @@
 ## Unreleased
 
 - Minimum supported Rust version (MSRV) is now 1.88.
+- Improve HTTP/2 upload throughput by increasing default flow control window sizes. [#3638]
+- Add `HttpServer::{h2_initial_window_size, h2_initial_connection_window_size}` methods for tuning. [#3638]
 - Add `HttpRequest::url_for_map` and `HttpRequest::url_for_iter` methods for named URL parameters. [#3895]
 - Ignore unparsable cookies in `Cookie` request header.
 - Add `experimental-introspection` feature to report configured routes [#3594]
@@ -13,6 +15,7 @@
 [#3895]: https://github.com/actix/actix-web/pull/3895
 [#3594]: https://github.com/actix/actix-web/pull/3594
 [#3918]: https://github.com/actix/actix-web/pull/3918
+[#3638]: https://github.com/actix/actix-web/issues/3638
 [#3562]: https://github.com/actix/actix-web/issues/3562
 [#3191]: https://github.com/actix/actix-web/issues/3191