diff --git a/release-notes-published/13.0.0.md b/release-notes-published/13.0.0.md
index 6daa96174f..7ab0679455 100644
--- a/release-notes-published/13.0.0.md
+++ b/release-notes-published/13.0.0.md
@@ -1,5 +1,7 @@
 A [companion blog post](https://forgejo.org/2025-10-release-v13-0/) provides additional context on this major release.
 
+This release contains [a regression](https://codeberg.org/forgejo/forgejo/issues/9421) when `RENDER_CONTENT_MODE = iframe` is set in `app.ini` that sometime forces the height to be 300px. It will be fixed in [Forgejo v13.0.1](https://codeberg.org/forgejo/forgejo/milestone/29090).
+
 <!--start release-notes-assistant-->
 
 ## Release notes