MediaWiki 1.38

MediaWiki 1.38 is a legacy stable release of MediaWiki. Consult the file for the full list of changes. It was deployed on Wikimedia Foundation wikis through incremental " wmf "-branches between September 2021 and March 2022. The 1.38.0 stable release came out on 2 June 2022. Download or checkout the  branch in Git to follow this release.

Configuration changes for system administrators
MediaWiki 1.38 is introducing a new system for configuration loading. The new system is fully compatible with the traditional way of configuring, but it offers some new features. Interested parties are encouraged to experiment with the new ways to load configuration and report any issues they come across.

New configuration

 * (T297708) – This setting can be used to control the maximum execution time for several expensive query pages (e.g. RecentChanges and UserContribs).
 * – This setting allows overriding browsers' automatic detection and handling of formats. It's initially used to prevent auto-linking of possible telephone numbers in wiki pages' output in Safari on iOS; this can be re-enabled if you wish, or locally extended for other browsers' quirks.
 * (T240685), , and – These provide configuration for a new  service with support for the  format, intended for integration with Prometheus.
 * – This setting allows inheriting permissions, both granted and revoked, from another group.
 * –  now has a  option to control for how long file metadata is cached.  Additionally, the default changed from 1 hour to 4 hours.
 * – This lets you set a list of preferred skins to be listed higher in Special:Preferences.
 * EXPERIMENTAL (see the docs on the new system to load configuration)
 * – A directory that contains site-specific configuration files. Setting this will enable multi-tenant ("wiki farm") mode, causing site-specific settings to be loaded based on information from the web request.
 * – The file extension to be used when looking up site-specific settings files in, such as  or.
 * – A callback function that returns the name of the wiki for the current request. Replaced by the MW_WIKI_NAME environment variable in 1.39. This is used in multi-tenant ("wiki farm") mode to determine which settings file to load from.
 * – This replaces the environment variable.
 * (T230211) – Force deferred updates to be run before sending a response to the client, instead of attempting to run them after sending the response.  Setting this to  is useful for end-to-end testing, to ensure that the effects of a request are visible to any subsequent requests, even if they are made immediately after the first one.  Note however that this does not ensure that database replication is complete, nor does it execute any jobs enqueued for later.
 * –  table schema migration stage, for normalizing  and  fields.

Changed configuration

 * and – These are now set later, so can no longer be used within  unless explicitly set in that file.
 * – This setting no longer takes as an option.
 * – This setting may now be set to to disable size checking before scaling.  Extensions can still override its value by using the  hook.
 * – Act as always-true.
 * – This no longer supports the string value for CDB files.
 * (T292321) –  Adjustments using this should be done with  instead.
 * – This is newly documented in.

Removed configuration

 * – This setting has been removed, as it was a flawed solution to the problem of locale dependence. MediaWiki will now always set a locale of  or  and works around the remaining problems of the  locale by not using  .  This follows the direction of PHP 8.0, which sets a locale of  by default instead of respecting.
 * (T293848) – Experiment removed, originally added in 1.35.
 * – We only support jQuery v3.
 * – This experimental feature has been removed. If you still need to use this feature, please see.
 * – Alias for.

Bundled extensions

 * (T191740) The extension is now bundled with MediaWiki.  This is an anti-abuse feature that allows privileged users to set specific actions to be taken when actions by users, such as edits or file uploads, match certain criteria.
 * (T232948) The extension is now bundled with MediaWiki.  This is a content feature that lets users create mathematical formulæ, written in a sub-set of LaTeX and rendered in MathML with a fallback SVG image.  By default, it will use Wikimedia's mathoid service to render each formula, but local rendering can be set up for network isolation or performance.
 * (T191743) The skin is now bundled with MediaWiki.  This is a simple, light-weight, and scalable skin that is particularly optimised for mobile use, and integrates well with the MobileFrontend extension (available separately), but can also be used as a regular desktop skin.

Other changes

 * (T284921) The "auto-number headings" feature was removed following a consultation, due to performance reasons.

New operator/developer features

 * The configuration mechanism changed substantially; you can read more about how.
 * EXPERIMENTAL: The environment variable can be used to specify the location of the settings file.  This allows alternative settings files to be loaded depending on the environment.  Settings files may be given as PHP files like the traditional  file, or they may use  or  format.  See
 * Added a maintenance script – This file enables the deletion of a given user's associated email address. It can be helpful for privacy-preserving operations.
 * The description array for constructing an now can use  to disable fields on a condition easily, supported expressions are the same as.
 * There is a new interface,, to allow you to mark file repos provided by an extension as supporting making API queries against the foreign file repo so that extensions like  that depend on this can stop hard-coding looking for specific class names.
 * EXPERIMENTAL Added support for an easy to configure multi-tenant ("wiki farm") mode: Settings for each site can be placed in a directory specified by .  Site detection is controlled by  and defaults to the requested host name.  For example, setting  would cause the settings for  to be loaded from "  ".  WARNING: YAML files under the Web root may be accessible to browsers, please take appropriate measures to protect them from access via HTTP.
 * Running QUnit tests for an individual test suite module is possible with, where is "MediaWiki" to run core's QUnit tests or the skin or extension name.
 * The module now has a  Less mixin.

New external libraries

 * was promoted from development-only.

Changed external libraries

 * Updated  from v0.42.0 to v0.43.2.
 * Updated  from 2.6.11 to 3.2.23.
 * Updated  from v0.3.0 to v0.4.0.
 * Updated  from 3.2.5 to 3.2.6.
 * Updated  from 7.2.0 to 7.4.1.
 * Updated  from 1.10.9 to 1.10.11.
 * Updated  from 1.9.2 to 1.10.0.
 * Updated  from 1.1.3 to 1.1.4.
 * Updated  from 0.10.5 to 0.11.1.
 * Updated  from 1.23.1 to 1.25.0.
 * Updated  from 0.5.0 to 0.5.1.
 * Updated  from 1.4.1 to 2.0.0.
 * Updated  from 3.0.2 to 4.0.0.
 * Updated  from 2.2.4 to 2.2.6.
 * Updated  from 3.0.2 to 4.0.0.
 * Updated  from v0.14.0-a14 to v0.15.0.
 * Updated  from 1.0.7 to 1.0.8.
 * Updated  from 1.1.0 to 1.2.0.
 * Updated  from 2.0.0 to 3.0.0.
 * Updated  from 3.2.0 to 4.0.1.

Changed development-only external libraries

 * Updated  from 2.16.0 to 2.18.0.
 * Updated  from 3.5.4 to 3.5.5.
 * Updated  from 1.5.4 to 1.5.5.
 * Updated  for PHP < 7.3 from 2.10.4 to 2.13.6.
 * Updated  for PHP >= 7.3 from 3.0.0 to 3.1.5.

Removed external libraries

 * , deprecated since MW 1.28; use instead.

Action API changes

 * New parameter on action=delete that allows you to delete the associated talk page of a subject page.
 * (T117549) New parameter for all API actions, for specifying language variant (akin to the existing  parameter for index.php).

Languages updated
MediaWiki supports over 400 languages. Many localisations are updated regularly. Below only new and removed languages are listed, as well as changes to languages because of Phabricator reports.


 * (T292166) Updated namespace names for the Lombard language.
 * (T299201) Changed the autonym of the (anp) language to अंगिका
 * (T298309) Changed the autonym of the (ab) language to аԥсшәа
 * (T302972) Changed the autonym of the (rn) language to ikirundi
 * (T220303) Show numbered lists with Burmese numerals in relevant languages
 * (T291899) Added language support for (hsn).
 * (T292612) Added language support for (ksw).
 * (T293656) Added language support for (gur).
 * (T294729) Added language support for (blk).
 * (T296286) Added language support for (sms).
 * (T296612) Added language support for (vmw).
 * (T296707) Added language support for (gaa).
 * (T297073) Added language support for (gld).
 * (T297074) Added language support for (nmz).
 * (T298075) Added language support for (nod).
 * (T298182) Added language support for (kea).
 * (T298385) Added language support for (yrl).
 * (T299329) Added language support for (fon).
 * (T300474) Added language support for (nyn).
 * (T302556) Added language support for (rsk).