diff --git a/doc/conffile.rst b/doc/conffile.rst
index c93eae99676..90f5f7a0b28 100644
--- a/doc/conffile.rst
+++ b/doc/conffile.rst
@@ -22,3 +22,4 @@ You can change the following configuration settings (must be under the ``[ownClo
 
 - ``maxLogLines`` (default:  ``20000``) -- Specifies the maximum number of log lines displayed in the log window.
 
+- ``chunkSize`` (default:  ``5242880``) -- Specifies the chunk size of uploaded files in bytes.