Board Thread:Questions and Answers/@comment-5845979-20130529010325/@comment-5643552-20130608012538

This script, specifically:

function UserNameReplace { if(typeof(disableUsernameReplace) != 'undefined' && disableUsernameReplace || wgUserName == null) return; $("span.insertusername").html(wgUserName); } addOnloadHook(UserNameReplace);