diff --git a/docs/releasenotes.rst b/docs/releasenotes.rst
index 2ce40fce8bb397fd066bd07a69b0e8352eb0095c..5f5a898386a67da178934487b9ff54de5f61026a 100644
--- a/docs/releasenotes.rst
+++ b/docs/releasenotes.rst
@@ -42,6 +42,13 @@ Dropped support for Debian 10 (Buster).
     parameter expects a list of IPv4 and IPv6 addresses (or
     subnets). Resolvable names can no longer be specified.
 
+* ``mail_server`` role
+
+  * Parameter ``mail_server_tls_protocols`` has been dropped and
+    replaced with parameter ``mail_server_minimum_tls_protocol``. Full
+    list of TLS protocols can no longer be specified, only the minimum
+    one.
+
 * ``wsgi_website`` role
 
   * Dropped support for Python 2.7. Only Python 3 is supported now.