Extension:ExtensionFunctions.php

This extension contains functions used in other extensions, which are intended to work regardless of the version of the MediaWiki core.

Description
ExtensionFunctions.php is a (rather useless) meta-include that Tim Starling introduced when he migrated a lot of extensions to a new special page call format between MediaWiki 1.6 and 1.7. Certain extensions that aren't directly cross-compatible with both require it.