Update changelog
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 4fdbda0..272ca34 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -190,6 +190,9 @@
 -  Libraries
    -  Further improved MIME type detection in the :doc:`File Uploading Library <libraries/file_uploading>`.
 
+-  Core
+   -  Added get_content_type for get current mime-types :doc:`Core Output Library <core/output>`.
+   
 -  Helpers
    -  url_title() performance and output improved. You can now use any string as the word delimiter, but 'dash' and 'underscore' are still supported.