diff --git a/CHANGES b/CHANGES
index d5d0026fa..e06a6faba 100644
--- a/CHANGES
+++ b/CHANGES
@@ -7,6 +7,8 @@ Dependencies
 Incompatible changes
 --------------------
 
+* #4467: html theme: Rename ``csss`` block to ``css``
+
 Deprecated
 ----------