[#5595] Added versionadded

Author: wouterj

reference/twig_reference.rst

@@ -383,6 +383,10 @@ Makes a technical name human readable (i.e. replaces underscores by spaces
 or transforms camelCase text like ``helloWorld`` to ``hello world``
 and then capitalizes the string).
 
+.. versionadded:: 2.3
+    Transforming camelCase text into human readable text was introduced in
+    Symfony 2.3.
+
 trans
 ~~~~~