Changelog: Fixed localization fallback bug in IncomingRequest

Author: markconnellypro

user_guide_src/source/changelogs/v4.6.5.rst

@@ -30,6 +30,8 @@ Deprecations
 Bugs Fixed
 **********
 
+- **Localization:** Fixed a bug in ``IncomingRequest::setLocale()`` that prevented falling back to valid, supported generic language code as locale.
+
 See the repo's
 `CHANGELOG.md <https://github.com/codeigniter4/CodeIgniter4/blob/develop/CHANGELOG.md>`_
 for a complete list of bugs fixed.