[ci skip] Add a changelog entry for PR #5510
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index f03794e..007e01c 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -14,6 +14,7 @@
 -  General Changes
 
    -  Updated :doc:`Query Builder <database/query_builder>` method ``limit()`` to allow ``0`` values.
+   -  Updated :doc:`Email Library <libraries/email>` and :doc:`Form Validation Library <libraries/form_validation>` to discard the results of failed ``idn_to_ascii()`` calls while validating e-mail addresses.
 
 Bug fixes for 3.1.9
 -------------------