You can add bug 2596.
Allow the max diff size to be customized.
Review Request #3134 — Created June 2, 2012 and submitted
Allow the max diff size to be customized. Some users weren't thrilled by the 1MB limit for diffs. This change makes this customizable, and defaults to unlimited diff sizes. Administrators can change this to any size they like in order to reduce load on the server.
Tested saving the setting. Unit tests all pass.