diff --git a/nixos/doc/manual/release-notes/rl-2605.section.md b/nixos/doc/manual/release-notes/rl-2605.section.md
index 8e4856ec0cd1..8648580fd898 100644
--- a/nixos/doc/manual/release-notes/rl-2605.section.md
+++ b/nixos/doc/manual/release-notes/rl-2605.section.md
@@ -72,6 +72,8 @@
 
 - `services.crabfit` was removed because its upstream packages are unmaintained and insecure.
 
+- `sing-box` has been updated to 1.13.0, which has removed some deprecated options.  See [upstream documentation](https://sing-box.sagernet.org/configuration/) for details and migration options.
+
 - `services.tandoor-recipes` now uses a sub-directory for media files by default starting with `26.05`. Existing setups should move media files out of the data directory and adjust `services.tandoor-recipes.extraConfig.MEDIA_ROOT` accordingly. See [Migrating media files for pre 26.05 installations](#module-services-tandoor-recipes-migrating-media).
 
 - `rustic` was upgraded to `0.11.x`, which contains breaking [changes to command-line parameters and configuration file](https://rustic.cli.rs/docs/breaking_changes.html#0110).