Extension:AjaxShowEditors

Ajax Show Editors extension allows you to see who is editing a page that you're editing.

Installation
Be sure to set $wgUseAjax = true; on LocalSettings.php if your MediaWiki is older than version 1.11.
 * 1) Download the files
 * 2) Run patch-editings.sql if you're using a MySQL database or patch-editings.pg.sql if you're using a PostgreSQL database
 * 3) Add require_once('extensions/AjaxShowEditors/Load.php'); to LocalSettings.php
 * 4) Installation can be verified through Special:Version