diff --git a/ChangeLog b/ChangeLog
index 6734cda3..c7bd1b2a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -17,6 +17,12 @@
 	functions in C++ that interoperate with the C API. See
 	examples/extend-c-api for more information.
 
+	* Bug fix from M. Holger: the default for /Columns in PNG filter
+	is 1, but libqpdf was acting like it was 0.
+
+	* Enhancement from M. Holger: add methods to Buffer to work more
+	easily with std::string.
+
 2023-12-10  Jay Berkenbilt  <ejb@ql.org>
 
 	* 11.6.4: release
diff --git a/manual/release-notes.rst b/manual/release-notes.rst
index 6fb88e93..5e41fef7 100644
--- a/manual/release-notes.rst
+++ b/manual/release-notes.rst
@@ -60,6 +60,9 @@ Planned changes for future 12.x (subject to change):
       C API to enable custom C++ code to interoperate more easily with
       the the C API. See ``examples/extend-c-api``.
 
+    - Add methods to ``Buffer`` to work more easily and efficiently
+      with ``std::string``.
+
 11.6.4: December 10, 2023
   - Bug fixes: