Extension Description Steward[1] Individual maintainer[2] Consultants[4] 3d Enables upload of three-dimensional model files, and supports thumbnailing and interactive viewing in Media Viewer.
Reader Growth
Support Level: pending. AbuseFilter Allows privileged users to set specific controls on actions by users, such as edits, and create automated reactions for certain behaviors
(Active volunteer) Marius Hoch, Daimona Eaytoy, se4598, Matěj Suchánek AdvancedSearch Enhances Special:Search by providing an advanced parameters form
WMDE Engineering (contact EMs) AntiSpoof Prevents creation of confusable usernames
Product Safety and Integrity Sam Reed ApiFeatureUsage Access API feature usage log summaries
MW Engineering (MW Interfaces) ArticleCreationWorkflow
Community Tech ArticlePlaceholder Provides a special page with Wikidata information about a certain topic, with invitation to create an article for the topic
WMDE Engineering (contact EMs) AutoModerator Allows moderators to configure automated prevention or reversion of bad edits based on scoring from a machine learning model
Moderator Tools Jason Sherman, Susana Cardenas Molinar Babel Adds a parser function to inform other users about language proficiency and categorize users of the same levels and languages
Language and Product Localization BetaFeatures Allows other extensions to register their beta features in the user preferences
Unassigned BounceHandler Allow MediaWiki to handle bounce email efficiently with VERP headers
Unassigned 01tonythomas, Jgreen (wmf) Calendar Creates a Calendar in pages
Unassigned CampaignEvents Adds tools for organizing events
Connection Team Campaigns Allows to track user account creations related to campaigns
Unassigned CategoryTree Provides a dynamic view of the wiki's category structure as a tree
Unassigned CentralAuth Allows to merge accounts into global accounts
MW Engineering (MW Platform) Zabe CentralNotice Adds a central sitenotice
Fundraising tech [primarily for FR use cases] CharInsert Create JavaScript character insert boxes
Editing Chart Renders charts
Reader Growth
Support Level: pending. CheckUser Allows a user with permissions to check which IPs are used by a given username and which usernames are used by a given IP
Product Safety and Integrity : WBrown (WMF) Dreamy Jazz CirrusSearch Implements searching for MediaWiki using Elasticsearch
Search Platform Cite Allows footnotes for citing sources and helps for correctly citing content in offline media
Editing Marius Hoch CiteThisPage Adds a special page that provides different citation formats for a particular article
Unassigned Marius Hoch Citoid Extension part of the Citoid service
Editing CLDR Import localisation data from CLDR
Language and Product Localization CodeEditor Provides a syntax-highlighting code editor for site & user JS, CSS and Lua pages, integrating with advanced edit toolbar
Editing Derk-Jan Hartman CodeMirror Provides syntax highlighting in MediaWiki's wikitext editor.
Community Tech MusikAnimal CommunityRequests A system for managing a wiki community's requests and suggestions for technical development.
Community Tech Cognate Centralises Wiktionary links into Wikidata
WMDE Engineering (contact EMs) Collection Allows organization of personal selections of pages in a collection that can be edited, persisted and optionally retrieved as PDF, ODF or DocBook (XML)
Reader Experience C. Scott Ananian originally: PediaPress CommonsMetadata Extracts metadata from commons pages
Unassigned, under review (T404286) CommunityConfiguration Allows editors with extended rights the ability to configure on-wiki functionality for all users.
Growth ConfirmEdit Adds CAPTCHAs for page saves and other user actions. Only QuestyCaptcha is supported.
Editing Emufarmers, Florianschmidtwelzow ContactPage Provides a contact form for visitors
MW Engineering (Content Transform)
SLA: Stable; Non-security patches not reviewed. Ammarpad ContentTranslation Allows editors to translate an article from one language to another with the help of machine translation and other aids.
Language and Product Localization CreditsSource Display source work credits in the page footer
Unassigned Dashiki Renders the JSON used to configure dashiki dashboards in a friendly HTML table
Data Engineering Disambiguator Enables the designation of disambiguation pages with a magic word
Unassigned DiscussionTools Tools to enhance discussion pages
Editing DismissableSiteNotice Allows users to close the sitenotice
Unassigned DonationInterface Provides fundraising mechanisms for collecting payments
Fundraising tech DynamicPageList (Wikimedia)

(aka Intersection)

Outputs a bulleted list of most recent items residing in a category, or an intersection of several categories
Unassigned Brian Wolff EasyTimeline Produces an embedded timeline image from special syntax inside ‎<timeline> tags.
Unassigned Antoine Musso (knows about the code) Echo Delivers notification messages to users. See also #MediaWiki core → Notifications.
Growth (Needs New Owner) Elastica Provides base elasticsearch functionality
Search Platform ElectronPdfService Converts wiki pages to PDFs using Electron.
WMDE Engineering (contact EMs) EmailAuth The extension allows secondary authentication via email.
Product Safety and Integrity Tgr, KHarlan (WMF), Roan Kattouw (WMF) EntitySchema Stores Shape Expressions Schemas on wiki pages (for Wikidata).
WMDE Engineering (contact EMs) EventBus Propagates change events to a RESTful service. Transports data between arbitrary applications, in the form of events that conform to versioned schemas.
Data Platform Engineering EventLogging Provides logging and validation of web analytics events
Experiment Platform EventStreamConfig Exposes event stream configs in an API endpoint. Can also be used to expose configs via ResourceLoader.
Data Engineering (Andrew Otto) ExtensionDistributor Enables the distribution of extensions from www.mediawiki.org
Unassigned Tim Starling ExternalGuidance Indicates to users that the wiki page being viewed is served through an external service, and provides ways to contribute back to the original wiki.
Language and Product Localization FeaturedFeeds Adds syndication feeds of wiki's featured content
MW Engineering (Content Transform)
SLA: Non-security patches not reviewed. For urgent non-security issues email wikitech-l. FileExporter Provides a link to export local files to another wiki that has the FileImporter extension.
WMDE Engineering (contact EMs) FileImporter Allows for the easy importing of a file from one wiki to another.
WMDE Engineering (contact EMs) FlaggedRevs Allows for article content management by "editor" and "reviewer" classes
Unassigned, under review (T185664) Aaron Schulz, Amir Sarabadani StructuredDiscussions (aka Flow) A modern discussion and collaboration system
Growth (Needs New Owner) FundraiserLandingPage Enables template parameters to be passed as querystring elements
Fundraising tech FundraisingTranslateWorkflow Locks down translation publishing rights on selected pages
Fundraising tech (Elliott Eggleston) FundraisingEmailUnsubscribe Donor-facing fundraising email unsubscribe form (on payments.wikimedia.org)
Fundraising tech Gadgets Allows users to enable JS-based, user-provided gadgets from their preferences page
Unassigned Roan Kattouw, Ammarpad, Timo Tijhof, SD0001 GeoCrumbs Adds a trail of bread crumbs to the page
Unassigned GeoData Adds geographical coordinates storage and retrieval functionality
Search Platform GlobalBlocking Allows IP addresses to be blocked on multiple wikis
Product Safety and Integrity : WBrown (WMF) GlobalCssJs Allows global CSS and JS on a "central" wiki to be loaded for all wikis in the farm
Unassigned GlobalPreferences Allows a user to decide which user preferences to set as global (wikifarm-wide) and which to keep local.
Community Tech GlobalUsage Enables viewing of global image use in a wiki farm with shared image repository
Unassigned, under review (T404286) GlobalUserPage Enables global (shared between wikis) user pages on a wiki farm
Unassigned GlobalWatchlist Allows a user to view changes to watched pages on multiple sites at once
Unassigned GoogleNewsSitemap Outputs a list of pages based on what categories they are in as an RSS feed or Google news sitemap
Unassigned Brian Wolff GrowthExperiments Provides newcomer features, such as a homepage with suggested tasks and finding mentors.
Growth GuidedTour Delivers guided tours
Growth (Needs New Owner) ImageMap Allows clickable HTML image maps
Editing ImageSuggestions Image recommendation features for experienced users
Unassigned, under review (T404286) InputBox Allows users to add predefined HTML forms to wiki pages
Reader Experience Insider Lists volunteer tour guides for travel destinations
Unassigned IPInfo Displays IP information for anti-vandalism purposes
Product Safety and Integrity IPReputation Provides access for fetching, logging, and acting on IP reputation data
Product Safety and Integrity : KHarlan (WMF), WBrown (WMF) Josa Automates josa part of Korean postposition process
Unassigned JsonConfig Provides a wiki-based JSON configuration system
MW Engineering (Content Transform)
SLA: Stable; Non-security patches not reviewed. Kartographer Allows adding maps to pages
MW Engineering (Content Transform)
SLA: 7 days Mateus Santos LabeledSectionTransclusion Enables marked sections of text to be transcluded
Unassigned LandingCheck Send users to localized landing pages with fallback options
Fundraising tech Linter Help users find out-dated bits of wikitext to fix them
MW Engineering (Content Transform)
SLA: 7 days LiquidThreads A structured discussion system for MediaWiki
Unassigned LoginNotify Notify users of suspicious logins
Product Safety and Integrity : KHarlan (WMF), Roan Kattouw (WMF) MapSources Gives access to several data and mapping sources
Unassigned MassMessage Allows users to send messages across wikis
Unassigned Math Renders mathematical formulas between <math> ... </math> tags
Editing Derk-Jan Hartman, Moritz Schubotz MediaModeration Checks uploaded media for possible child exploitation content. Product Safety and Integrity : WBrown (WMF) MediaSearch An alternative, media-focused way to display search results through the Special:MediaSearch page.
Reader Growth
Support Level: pending. MobileApp Serves styles and scripts for use in the Wikimedia native apps
Apps, MW Engineering (Content Transform)
SLA: 14 days MobileFrontend Optimizes content for mobile experiences.
Reader Growth
Support Level: active maintenance. See OWNERS.md for stewardship details of components within the extension. MultimediaViewer Provides a better experience to users when they click on thumbnails in a page
Reader Growth
Support Level: pending. MultiTitle Gives the appearance of one page having multiple titles.
Pending: phab:T404461 C. Scott Ananian, Tbodt NavigationTiming Logs perceived latency measurements from client-side
Unassigned formerly Performance NearbyPages Provides Special:Nearby Reader Growth
Support Level: pending. NetworkSession A SessionProvider for api requests based on configured ip address and a secret token
Search Platform Erik Bernhardson Newsletter Adds a preference for newsletter subscription
(Active volunteer) 01tonythomas, Brian Wolff (for emergency issues) NewUserMessage Adds a message to newly created user's talk pages
Growth (Needs New Owner) Nuke Gives sysops the ability to mass delete pages
Moderator Tools OATHAuth An HMAC based One Time Password extension, providing two-factor authentication
Product Safety and Integrity Taavi Väänänen OAuth Allow users to safely authorize another application (Consumer) to use the MediaWiki api on their behalf
MW Engineering (MW Platform) Tgr (WMF), Ammarpad OAuthRateLimiter Implements an OAuth hook to add rate limit values to the OAuth JSON Web Token (JWT)
MW Engineering (MW Platform) ORES Integrates data from the ORES project into the RecentChanges view
Machine Learning/Scoring Platform PageAssessments Stores assessments of pages made by WikiProjects
Community Tech PagedTiffHandler Handles TIFF files, including multi-paged images
MW Engineering (Content Transform)
SLA: 14 days PageImages Stores information about images representing a page
Pending stewardship review (phab:T252249) PageNotice Displays notices at the top of all pages in a namespace
(Active volunteer) TTO PageTriage Facilitates reviewing and approving new pages
Moderator Tools Novem Linguae Sohom Datta PageViewInfo Provides fancy looking graphs of Wikimedia page view data
Unassigned ParserFunctions Enhances parser with logical and string functions
MW Engineering (Content Transform) Jackmcbarn, Tim Starling? ParserMigration Allows users to preview the appearance of articles with the new Parsoid parser
MW Engineering (Content Transform) PdfHandler Handles PDF files like multipage DJVU
MW Engineering (Content Transform)
SLA: 14 days bawolff PersonalDashboard Houses experiments for building a dashboard for moderators
Moderator Tools Phonos Text to speech parser and inline audio player
Language and Product Localization Community Tech Poem Adds <poem> tag for poem formatting
Reader Experience Popups Displays popups when users hover over article links (aka. Hovercards)
Reader Growth
Support level: pending Produnto Manages Scribunto modules and gadgets deployed on MediaWiki wikis.
MW Engineering (Content Transform) ProofreadPage Helps proofreading of books.
(Active volunteer) Thomas PT (Tpt), Sohom Datta (mostly on the Javascript/interface side of things) PropertySuggester Provides suggested properties when a user tries to add new statements to a Wikidata item.
WMDE Engineering (contact EMs) QuickSurveys Provides in-article quick surveys or external survey to poll readers for opinions.
Reader Experience
SLA: 14 days Consult Reader Experience for large architectural changes or UBN bugs.

Others are feel free to contribute and merge changes to this extension.

Quiz Quiz building tool adopted on the Wikiversity
Unassigned ReaderExperiments For prototyping and testing new features to enhance reader engagement.
Reader Growth
Support Level: active development. ReadingLists Provides an API for storing and retrieving private lists of pages.
Reader Experience RelatedArticles Parser function to associate related articles (cf. Wikivoyage)
Reader Growth
Support level: pending RealMe Allows verifying URLs used on user pages
(Active volunteer) Taavi Väänänen ReportIncident Allow users to report incidents of harassment and abuse.
Product Safety and Integrity RevisionSlider Visualizes revision history
WMDE Engineering (contact EMs) RSS Displays RSS feeds on a wiki page
Unassigned SandboxLink Provides a link in personal tools to a per-user sandbox
Unassigned Matma Rex (Bartosz Dziewoński) SecureLinkFixer Automatically rewrites URLs to HTTPS if domain always requires HTTPS (T200745)
Unassigned Legoktm, formerly Core Platform Score Allows rendering of musical scores with en:LilyPond
Reader Experience Alexander Klauer, Ebe123 Scribunto Provides a framework for embedding scripting languages into MediaWiki pages
Unassigned Tim Starling, Victor Vasiliev, Jackmcbarn, cscott, formerly Core Platform; possibly Content Transform SearchExtraNS Searches extra specified namespaces if no direct match is found
Unassigned SearchVue Vue.js augmentations and improvements to Special:Search
Reader Growth
Support Level: unsupported, pending decommission. SecurePoll Extension for elections and surveys
Product Safety and Integrity Huji, SD0001, Novem Linguae ShortUrl Adds a special page that redirects to an article based on the given base36-encoded ID
Unassigned, under review (T404286) SiteMatrix A special page with a matrix of all Wikimedia sites
Unassigned SpamBlacklist Provides a regex-based spam filter
Unassigned, under review (T224921) SubPageList3 Provides a splist tag to list the subpages of a page
Unassigned SubpageSortkey Changes the default sortkey to have something to do with the subpages
Unassigned Brian Wolff SyntaxHighlight Provide a wikitext feature to embed source code examples on wiki pages with syntax highlighting. Powered by Pygments via Shellbox, and includes a VisualEditor plugin.
Editing SD0001 TemplateData Creates and extracts data about templates and their usage
Editing TemplateSandbox Enables page previews using sandboxed templates
Unassigned Jackmcbarn TemplateStyles Allows for loading sanitized CSS stylesheets from a template
MW Engineering (Content Transform)
SLA: Non-security patches not reviewed. Gergő Tisza TemplateWizard Adds a popup dialog box for adding template code to wikitext.
Community Tech Samwilson TestKitchen Provides APIs for instrumentation and experimentation.
Experiment Platform Sam Smith, Santiago Faci, Clare Ming TextExtracts Provides API with plain-text or limited HTML extracts of page content
Pending stewardship review (phab:T256505) Thanks Send a public "Thanks" to the author of an edit.
Growth (Needs New Owner) TheWikipediaLibrary Notifies users of their eligibility for the Wikipedia Library when they cross the edit count and account age thresholds
Moderator Tools Jason Sherman, Susana Cardenas Molinar TimedMediaHandler Provides integrated support for server side transcoding, WebM, Ogg Theora, Vorbis, Speex and Timed Text
Reader Growth
Support Level: pending. Brooke Vibber TitleBlacklist Blocks the creation of pages matching a regular expression blacklist
Unassigned Jackmcbarn TocTree Adds options for floated or expanded table of contents (cf. Wikivoyage)
Unassigned TorBlock Automatically applies restrictions to Tor exit nodes with access to the wiki's front-door server
Unassigned formerly Core Platform. Translate Enables in-wiki translation and proofreading
Language and Product Localization TranslationNotifications Allows translators sign up for translation notifications
Language and Product Localization TrustedXFF Handles trusted proxy addresses (XFF)
Unassigned formerly Core Platform. TwoColConflict Provides an interactive two-column edit conflict resolution tool
WMDE Engineering (contact EMs) UniversalLanguageSelector Allows users to select a language and configure its support in an easy way.
Language and Product Localization UploadsLink Provides a link in personal tools to a user's uploads
Unassigned Jdlrobson UploadWizard Helps people upload media to Commons.
Unassigned, under review (T404286) UrlShortener Provides a basic URL shortening service
Unassigned formerly Core Platform. VisualEditor Enables a rich-text editor for wiki pages (see also Parsoid)
Editing WikibaseClient Client for structured data repository
WMDE Engineering (contact EMs) WikibaseRepository Structured data repository
WMDE Engineering (contact EMs) WikibaseCirrusSearch Implements searching for Wikibase repositories using Elasticsearch
Search Platform WikibaseLexeme Structured lexicographical data
WMDE Engineering (contact EMs) WikibaseLexemeCirrusSearch Implements searching for Wikibase Lexemes using Elasticsearch
Search Platform WikibaseMediaInfo Wikibase extension to manage structured metadata of media files
Unassigned, under review (T404286) WikibaseQualityConstraints Wikibase extension to check editor-defined constraints on entity data
WMDE Engineering (contact EMs) Wikidata.org Specific code for Wikibase as running on Wikidata.org WMDE Engineering (contact EMs) WikidataPageBanner Adds pagewide banners at the top of pages in specified namespaces on a wiki.
Reader Experience WikiEditor Provides an extendable wikitext editing interface and many feature-providing modules
Editing Derk-Jan Hartman wikihiero Enables the use of hieroglyphs with additional syntaxes
Reader Experience Max Semenik Jdlrobson WikiLambda Enables a wiki to host functions written, managed, and evaluated by users
Abstract Wikipedia WikiLove Makes it easy to add positive feedback to user talk pages
Unassigned Jdlrobson WikimediaApiPortalOAuth The WikimediaApiPortalOAuth extension is designed to connect the API Portal with the OAuth server on Meta-Wiki. It provides a user interface to create and manage OAuth 2.0 clients. Unassigned formerly Core Platform. WikimediaBadges Default themes to display badges on Wikimedia projects
WMDE Engineering (contact EMs) WikimediaCampaignEvents Wikimedia-specific add-ons for the CampaignEvents extension
Connection Team WikimediaCustomizations Wikimedia-specific code that doesn't fit elswhere
MediaWiki Platform Team See OWNERS.md WikimediaEvents Event instrumentations and wiring for Wikimedia Foundation sites
Experiment Platform See OWNERS.md for individual owners of each schema. WikimediaIncubator Adds functions meant for Wikimedia Incubator
(Active volunteer) Jon Harald Søby (and currently inactive: Robin Pepermans, Hydriz, Ebe123) WikimediaMaintenance Various WMF-specific maintenance scripts
Unassigned Sam Reed WikimediaMessages Adds Wikimedia specific messages and grammar, as well as Wikimedia specific overrides for license related messages
Unassigned Maarten Dammers Wikisource
Community Tech Tpt Sohom Datta Wikistories
Language and Product Localization (SBisson) XAnalytics Communicates analytic information for WMF to logging infrastructure
Unassigned