From mediawiki.org
MediaWiki extensions manual
Global CSS/JS
Release status: stable
Implementation Skin , MyWiki
Description Allows global CSS and JS on a "central" wiki to be loaded for all wikis in the farm
Latest version 3.4.0
MediaWiki 1.31+
PHP 7.0+
License GNU General Public License 2.0 or later
Help Help:Extension:GlobalCssJs
  • $wgUseGlobalSiteCssJs
  • $wgGlobalCssJsConfig
Quarterly downloads 12 (Ranked 136th)
Translate the GlobalCssJs extension
Issues Open tasks · Report a bug

The GlobalCssJs extension allows loading CSS and JavaScript (JS) from a central wiki.

It supports wiki farm-wide and individual site-wide "MediaWiki:Global.js"/"MediaWiki:Global.css" pages and per-user "User:$username/global.js"/"User:$username/global.css" pages on a specified central wiki. The term "global" is used to mean across a wiki farm (compare with Extension:GlobalUsage) and the capitalization ("Css" and "Js") is due to MediaWiki extension naming conventions.

If you are not using shared user tables or CentralAuth, this extension can open up a XSS vector, which allows other users to hijack the user's account, among other things. See #Hook for information on how to integrate your authentication extension with this one.


  • Download and move the extracted GlobalCssJs folder to your extensions/ directory.
    Developers and code contributors should install the extension from Git instead, using:cd extensions/
    git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/GlobalCssJs
  • Add the following code at the bottom of your LocalSettings.php file:
    wfLoadExtension( 'GlobalCssJs' );
  • Configure as required.
  • Yes Done – Navigate to Special:Version on your wiki to verify that the extension is successfully installed.



Whether to enable MediaWiki:Global.js/MediaWiki:Global.css pages. By default enabled.

$wgUseGlobalSiteCssJs = true;


ResourceLoader configuration of the global wiki. By default, no global wiki is specified.

$wgGlobalCssJsConfig = [
	'wiki' => false,
	'source' => false,
  • 'wiki' should be set to the database name of the central wiki.
  • 'source' should be the name of the ResourceLoader source.

An example configuration might look like:

$wgGlobalCssJsConfig = [
	'wiki' => 'metawiki',
	'source' => 'metawiki',
// 'source' must point to a key in $wgResourceLoaderSources, like so:
// $wgResourceLoaderSources['metawiki'] = array(
//     'apiScript' => 'https://meta.wikimedia.org/w/api.php',
//     'loadScript' => 'https://meta.wikimedia.org/w/load.php',

To test it our locally without a central repository, point it at the local wiki, like so:

$wgGlobalCssJsConfig = [
	'wiki' => $wgDBname,
	'source' => 'local',


If you are not using shared user tables for managing users, you can use a hook to state whether a user on one wiki is equal to another.

public static function onLoadGlobalCssJs( User $user, $centralWiki, $localWiki );

$centralWiki is the wiki the JS/CSS is being taken from, and $localWiki is the current wiki the request is being executed on. The hook will not be called if $centralWiki === $localWiki.

The function should return true if the users are the same, and false if they are not. An example subscriber can be found in the CentralAuth extension.


See Help:Extension:GlobalCssJs for details.