Extensions (such as the hieroglyphic module WikiHiero) are distributed
separately. Drop them into this extensions directory and enable as
per the extension's directions.

You can find a list of extensions and documentation on the MediaWiki website:
    https://www.mediawiki.org/wiki/Category:Extensions


If you are a developer, you want to fetch the extension tree in another
directory and make a symbolic link:

 mediawiki/extensions$ ln -s ../../extensions-trunk/FooBarExt

Most extensions are available through Git:
    https://gerrit.wikimedia.org/r/#/admin/projects/
    https://git.wikimedia.org/project/mediawiki

Old extensions are on Subversion:
    https://svn.wikimedia.org/svnroot/mediawiki/trunk/extensions/


Please note that under POSIX systems (Linux...), parent of a symbolic path
refers to the link source, NOT to the target! You should check the env
variable MW_INSTALL_PATH in case the extension is not in the default location.

The following code snippet lets you override the default path:

 $IP = getenv( 'MW_INSTALL_PATH' );
 if( $IP === false ) {
	$IP = __DIR__ . '/../..';
 }
 require_once "$IP/maintenance/Maintenance.php"; // a MediaWiki core file