diff --git a/changelogs/client_server.rst b/changelogs/client_server.rst
index 44d41f4e4..697b02c1a 100644
--- a/changelogs/client_server.rst
+++ b/changelogs/client_server.rst
@@ -41,6 +41,8 @@ Unreleased changes
     (`#1245 <https://github.com/matrix-org/matrix-doc/pull/1244>`_).
   - Describe ``StateEvent`` for ``/createRoom``
     (`#1329 <https://github.com/matrix-org/matrix-doc/pull/1329>`_).
+  - Clarify that clients must leave rooms before forgetting them
+    (`#1378 <https://github.com/matrix-org/matrix-doc/pull/1378>`_).
 
 - Changes to the API which will be backwards-compatible for clients: