Release notes/1.39

= MediaWiki 1.39 =

MediaWiki 1.39.0-rc.0
THIS IS NOT A RELEASE YET

MediaWiki 1.39 is a pre-release testing branch, and is not recommended for use in production.

Upgrading notes for 1.39
Don't forget to always back up your database before upgrading!

See the file UPGRADE for more detailed per-version upgrade instructions from the oldest supported upgrading version, MediaWiki 1.31.

Some specific notes for MediaWiki 1.39 upgrades are below:
 * (phab:T278139) Drop PHP 7.3 support in MediaWiki 1.39; require 7.4.3 or higher.

For notes on 1.38.x and older releases, see HISTORY.

Configuration changes for system administrators in 1.39

 * The default serialization method for file meta-data has been changed to JSON. You can revert it to PHP by setting the 'useJsonMetadata' property to false in $wgLocalFileRepo.
 * The DBO_SSL flag in $wgDBservers and $wgLBFactoryConf has been deprecated in favour of a boolean "ssl" parameter.
 * $wgMangleFlashPolicy is deprecated and is no longer functional. Users who are somehow still using Flash as a browser extension will be exposed to CSRF vulnerabilities.

New configuration

 * $wgAutoCreateTempUser – configures automatic user creation on page save.
 * $wgCopyUploadAllowOnWikiDomainConfig – Configures if administrators can use the MediaWiki:Copyupload-allowed-domains system message to define which domains can be used with the upload-by-url tool.
 * $wgLBFactoryConf['configCallback'] can be set to a callback function that returns an array with keys to update in $wgLBFactoryConf. This can be used to update the database configuration on the fly, e.g. to take replica hosts out of rotation.
 * $wgCdnMatchParameterOrder can be set to false if MediaWiki is behind a CDN that re-orders query parameters. This will make the code that matches request URLs to canonical CDN URLs insensitive to parameter order.
 * $wgMultiShardSiteStats – split site_stats across multiple rows. Only useful for very large, heavily edited wikis. (phab:T306589)

Changed configuration

 * $wgInvalidUsernameCharacters now contains the char '>', reserved delimiter for external user names.

Removed configuration

 * $wgMultiContentRevisionSchemaMigrationStage - Migration is over, was deprecated since 1.35.
 * $wgWikiFarmSiteDetector – experimental setting removed without replacement. Use the MW_WIKI_NAME environment variable to specifiy the name of the site to load configuration for. Using the WIKI_NAME environment variable for this purpose is deprecated.
 * $wgParserCacheUseJson - the ParserCache now always uses JSON serialization. Reading old non-JSON cache entries is still supported. The setting had been deprecated since 1.36.
 * $wgAllowJavaUploads - To allow uploads of JAR files, remove application/java from $wgMimeTypeExclusions.
 * $wgMaxRedirects has been removed. This feature never worked as intended, see phab:T296430.
 * $wgElementTiming has been removed. This feature was experimental, and disabled by default.
 * $wgPriorityHints and $wgPriorityHintsRatio have been removed. This feature was experimental, and disabled by default.
 * $wgIncludeLegacyJavaScript has been removed. Note that no functionality was removed in this release. Most former "wikibits" functions were removed after deprecation in previous releases. The remaining functions, such as importScript, are available unconditionally.
 * $wgActorTableSchemaMigrationStage has been removed. Migration is over.
 * In $wgObjectCaches, globalKeyLB and localKeyLB are no longer supported.
 * $wgLegacySchemaConversion - This global configuration has been removed because it was unused.
 * $wgInterwikiPrefixDisplayTypes - This global configuration has been removed because it was unused.

New user-facing features in 1.39

 * Optional automatic user creation on page save ($wgAutoCreateTempUser)
 * Administrators now have the option to delete/undelete the associated "Talk" page when they are (un)deleting a given page. `deletetalk` and `undeletetalk` options were added to the 'delete' and 'undelete' action APIs in MW 1.38.
 * `=` is now a wikitext built-in magic word, expanding to `=`. This is conventionally used as an escape mechanism to allow the use of `=` in unnamed template arguments. Defining Template:= to expand to something other than `=` has been deprecated since 1.36, with affected pages put into a special tracking category for migration.
 * (phab:T284020) Bot passwords are now supported when using the REST API.

New developer features in 1.39

 * Added optional $size param to SearchResultProvideThumbnail hook.
 * SearchResultProvideThumbnail hook interface moved from MediaWiki\Rest\Hook namespace to MediaWiki\Search\Hook.
 * JsonValidateSaveHook has been added to allow extensions to set additional pre-save validations for specific JSON pages (phab:T313254).
 * Added 'PermissionErrorAudit' hook, enabling extensions to audit permission errors on specfic actions (for instance, account registration failed attempts due to a block (phab:T306018)).

New external libraries

 * Added Codex v0.1.1. This replaces the now deprecated wvui library.

New development-only external libraries

 * Updated QUnit from 2.18.0 to 2.18.2.

Changed external libraries

 * Updated jQuery from v3.6.0 to v3.6.1.
 * Updated OOUI from v0.43.2 to v0.44.3.
 * Updated composer/semver from 3.2.6 to 3.3.2.
 * Updated symfony/polyfill-php73 from 1.25.0 to 1.26.0.
 * Updated symfony/polyfill-php80 from 1.25.0 to 1.26.0.
 * Updated symfony/yaml from 5.4.3 to 5.4.10.
 * Updated vue/compat from 3.2.23 to 3.2.37.
 * Updated wikimedia/base-convert from 2.0.1 to 2.0.2.
 * Updated wikimedia/ip-set from 3.0.0 to 3.1.0.
 * Updated wikimedia/minify from 2.2.6 to 2.3.0.
 * Updated wikimedia/php-session-serializer from 2.0.0 to 2.0.1.
 * Updated wikimedia/running-stat from 1.2.1 to 2.1.0.
 * Updated wikimedia/scoped-callback from 3.0.0 to 4.0.0.
 * Updated wikimedia/services from 2.0.1 to 3.0.0.
 * Updated wikimedia/timestamp from 3.0.0 to 4.0.0.
 * Updated wikimedia/xmp-reader from 0.8.1 to 0.8.3.

Changed development-only external libraries

 * Updated composer/spdx-licenses from 1.5.5 to 1.5.6.
 * Updated doctrine/dbal for PHP < 7.3 from 2.13.6 to 2.13.9.
 * Updated doctrine/dbal for PHP >= 7.3 from 3.1.5 to 3.4.2.

Bug fixes in 1.39

 * (phab:T314013) $wgExtraNamespaces no longer overrides canonical namespace names specified in extension.json files. While this setting can still be used to rename extension-defined namespaces, system administrators may need to run namespaceDupes.php after upgrading.

Action API changes in 1.39

 * New `undeletetalk` parameter on action=undelete that allows you to restore all revisions of the associated talk page.

Languages updated in 1.39
MediaWiki supports over 350 languages. Many localisations are updated regularly. Below only new and removed languages are listed, as well as changes to languages because of Phabricator reports.


 * Actual localization was added for several languages, which were already in Names.php and even used for a Wikipedia:
 * (phab:T313200) Added language support for Rundi (Kirundi, rn).
 * (phab:T310976) Added language support for Tumbuka (ChiTumbuka, tum).
 * (phab:T314270) Added language support for Kanuri (kr).
 * (phab:T313199) Added language support for Sylheti (syl).
 * (phab:T311975) Added language support for Ghanaian Pidgin (gpe).
 * (phab:T307080) Added language support for Okinawan (ryu).
 * (phab:T307887) Added language support for Mooré (mos).
 * (phab:T308813) Added language support for Nigerian Pidgin (pcm).
 * (phab:T309763) Added language support for Tai Nüa (tdd).
 * (phab:T310040) Added language support for Fante (fat).
 * (phab:T311034) Added language support for Campidanese Sardinian (sro).
 * (phab:T315406) Fix the autonym of the Iñupiaq language to "Iñupiatun".
 * (phab:T315677) Removed French fallback from the Fula language (ff).
 * (phab:T304920) In Swahili, the "Media" namespace is now "Media", as in English, and the "File" namespace is now "Faili". The old name of the "File" namespace was "Picha", which has been kept for backwards compatibility. If you manage a wiki in Swahili, and you use "Faili:" as a namespace anywhere in wikitext, and you mean to use it as "Media:", these need to be replaced to "Media:".
 * (phab:T309866) Some namespace translations were updated for Kyrgyz (ky). The old ones are retained as aliases for backwards compatibility.
 * (phab:T117845) Started the renaming of the language codes for Serbian from sr-ec and sr-el to sr-cyrl and sr-latn.

Breaking changes in 1.39

 * Basic non-JavaScript (Grade C) support has been dropped for Internet Explorer 9-10, Firefox 27-38, and Android 4.3-4.4.
 * The following methods, deprecated since 1.37, have been removed from IDatabase:
 * ::fetchObject
 * ::fetchRow
 * ::numRows
 * ::freeResult
 * Title::getDefaultNamespace, deprecated since 1.37, has been removed.
 * The DBPrimaryPos class alias 'DBMasterPos' has been removed.
 * The global function wfGetLB, deprecated since 1.27, has been removed.
 * Passing a db to BlockRestrictionStore::loadByBlockId is no longer supported. BlockRestrictionStoreFactory should be used to fetch a correct BlockRestrictionStore instead. This was deprecated since 1.38.
 * The global function wfGetCache, deprecated since 1.32, has been removed. You can use ObjectCache::getInstance instead.
 * The global function wfGetMainCache, deprecated since 1.32, has been removed. You can use ObjectCache::getLocalClusterInstance instead.
 * MovePage::__construct now requires that all parameters be passed. The fallback to MediaWikiServices emitted deprecation notices since 1.37.
 * WikiPage::doEditContent, deprecated since 1.32, was removed.
 * WikiPage::prepareContentForEdit now requires a UserIdentity parameter to be provided. Not providing one has been deprecated since 1.37.
 * EventRelayerKafka, deprecated in 1.38, was removed.
 * MediaWiki\Logger\Monolog\KafkaHandler, deprecated in 1.38, was removed.
 * The "trace" option of SectionProfiler, deprecated in 1.38, was removed.
 * The global function wfWikiID, deprecated since 1.35, has been removed.
 * Database::wasKnownStatementRollbackError was removed. Subclasses should override isKnownStatementRollbackError instead.
 * Database::wasQueryTimeoutError was removed. Subclasses should override isQueryTimeoutError instead.
 * Database::buildSuperlative has been removed without deprecation.
 * The following methods, deprecated in 1.37, have been removed:
 * Linker::setStubThreshold, ::getStubThreshold.
 * LinkRendererFactory::createForUser.
 * ParserOptions::getStubThreshold, ::setStubThreshold.
 * Changes to ResourceLoader modules:
 * The mediawiki.viewport module, deprecated in 1.37 has been removed. Use IntersectionObserver instead.
 * If you manage a wiki in Swahili, and you use "Faili:" as a namespace anywhere, and you mean to use it as "Media:", replace it with "Media:". See phab:T304920.
 * Changes to skins:
 * Skin::getCopyrightIcon, ::getPoweredBy, deprecated in 1.37 have been removed.
 * Skin::bottomScripts soft deprecated in 1.37, was hard deprecated. Skins using SkinTemplate must set bodyOnly as a skin option and remove lines of code generating html, body and head elements.
 * Skin::makeSearchButton and Skin::makeSearchInput were deprecated in 1.38. Use SkinTemplate methods with the same name or Skin::getTemplateData instead.
 * Styles for the HTML classes `warningbox`, `errorbox` and `successbox` have been removed in favor of Html class methods.
 * The feature `legacy` used inside ResourceLoaderSkinModule, deprecated in 1.37, will no longer ship any styles.
 * Skin::getSkinStylePath, deprecated since 1.36, has been removed.
 * Skin::getPortletData has been made private.
 * SkinTemplate::getPersonalToolsList, deprecated in 1.35 has been removed.
 * The following SkinTemplate template data, deprecated in 1.37, have been removed:
 * poweredbyico
 * copyrightico
 * The following hooks, deprecated in 1.37, have been removed:
 * SkinGetPoweredBy: SkinGetPoweredByHook
 * The following hooks are deprecated and replaced with SkinTemplateNavigation::Universal:
 * SkinTemplateNavigation::SpecialPage
 * SkinTemplateNavigation
 * PersonalUrls
 * The mediawiki.skinning.content.externallinks module, which was deprecated in 1.36, has been removed. Skins that still rely on it will lose the icon styling of external links by type.
 * Experimental wiki farm support: Automatic detection of the requested site within a wiki farm based on the requested domain has been removed. Use the MW_WIKI_NAME environment variable to specify the name of the site  to load configuration for. Using the WIKI_NAME environment variable for this  purpose is deprecated. This is only relevant if you have been using  $wgWikiFarmSettingsDirectory to load wiki farm config.


 * MWExceptionHandler::installHandler was marked @internal and had required arguments added. This method is intended for use in bootstrap code and is unused in known extensions.


 * MWException::useOutputPage was made private without deprecation. This method was apparently only public for testing and is unused in known extensions.


 * Calling getId on a User or UserIdentityValue from the wrong wiki, deprecated since 1.36, now throws an exception.


 * The following methods have been removed from ExtensionRegistry without deprecation and without replacement. They had been introduced in 1.35 for use in the testing framework, and were not in use by any known extension:
 * exportAutoloadClassesAndNamespaces
 * exportTestAutoloadClassesAndNamespaces
 * The MWNamespace class, deprecated since 1.34, has been removed. Use the NamespaceInfo service instead.


 * The UnknownContent and UnknownContentHandler class aliases have been removed, use FallbackContent and FallbackContentHandler instead.


 * IResultWrapper::next now returns void, to match the Iterator interface that it implements. fetchObject has the same behavior as next used to.


 * In HTMLForm HTMLAutoCompleteSelectFields, the parameters 'autocomplete' and 'autocomplete-messages', which were deprecated in MediaWiki 1.29, were removed. Instead, use 'autocomplete-data' and 'autocomplete-data-messages'.


 * The global $wgParser, deprecated in 1.32, was removed. Use MediaWikiServices::getInstance->getParser instead.


 * ParserOutput::setText will now set the ParserOutput's text to null if given null. Previously it did nothing if given null.


 * The default value for the first argument to the ParserOutput constructor is now null instead of .


 * IDatabase::lockTables and IDatabase::unlockTables, deprecated since 1.38, have been removed.


 * The $context parameter to `new HTMLForm( … )` and `HTMLForm::factory( … )` is now required.


 * The class alias for revision related classes in namespace MediaWiki\Storage has been removed. Classes are IncompleteRevisionException, MutableRevisionRecord, MutableRevisionSlots, RevisionAccessException, RevisionArchiveRecord, RevisionFactory, RevisionLookup, RevisionRecord, RevisionSlots, RevisionStore, RevisionStoreRecord, SlotRecord, and SuppressedDataException.


 * Calling getBy on an AbstractBlock from the wrong wiki, deprecated since 1.38, now throws an exception.


 * Passing a MediaWiki\Linker\LinkTarget to EditPage::makeTemplatesOnThisPageList or TemplatesOnThisPageFormatter::format is no longer supported, a MediaWiki\Page\PageIdentity is required.


 * The deprecated class alias FakeConverter has been removed, use TrivialLanguageConverter instead.


 * The deprecated ApiQueryContributions class alias has been removed, use ApiQueryUserContribs instead.


 * The deprecated MediaWiki\Special\SpecialPageFactory class alias has been removed, use MediaWiki\SpecialPage\SpecialPageFactory instead.


 * The following skin modules, deprecated in 1.37, have been removed:
 * mediawiki.skinning.elements
 * mediawiki.skinning.content
 * mediawiki.toc.styles
 * mediawiki.legacy.config
 * mediawiki.legacy.shared
 * mediawiki.legacy.commonPrint
 * FileModule::compileLessFile, deprecated since 1.35, has been removed. Use ::compileLessString instead.


 * LogFormatter::styleRestricedElement, deprecated since 1.37, has been removed. Use ::styleRestrictedElement instead.


 * Title::isNamespaceProtected, deprecated in 1.34, has been removed.
 * ApiStashEdit::parseAndStash, deprecated in 1.34, has been removed.
 * LinkCache::forUpdate, deprecated in 1.34, has been removed.
 * Passing null instead of a NamespaceInfo instance to LinkCache::__construct is not supported anymore. It is recommended to request an instance from the service container.


 * ApiQueryBase::showHiddenUsersAddBlockInfo, deprecated in 1.34, has been removed. Use ApiQueryBlockInfoTrait instead.


 * ApiQueryBase::prefixedTitlePartToKey, deprecated in 1.35, has been removed. Use ::parsePrefixedTitlePart instead.


 * ExternalStoreDB::getSlave, deprecated in 1.34, has been removed. Use ExternalStoreDB::getReplica instead.


 * ChangesListSpecialPage::checkStructuredFilterUiEnabled and SpecialWatchlist::checkStructuredFilterUiEnabled now support UserIdentity as the only argument. Passing Config argument was deprecated in 1.34.


 * DatabaseUpdater::ifNoActorTable, deprecated in 1.35, has been removed. Use ::ifTableNotExists instead.


 * MediaWiki\Revision\RevisionStoreFactory::getRevisionStore was documented to allow passing bool true as a dbDomain, this is no longer possible, because that is an invalid value for a dbDomain.


 * LinkHolderArray::__construct had its signature changed. The class was marked internal in 1.35.


 * SpecialMute::isTargetBlacklisted, deprecated in 1.35, has been removed. Use ::isTargetMuted instead.


 * WebRequest::checkUrlExtension, deprecated in 1.35, has been removed.
 * ContentHandler::cleanupHandlersCache, deprecated in 1.35, has been removed.
 * SpecialVersion::getExtAuthorsFileName, deprecated in 1.35, has been removed. Use MediaWiki\ExtensionInfo::getAuthorsFileName.


 * SpecialVersion::getExtLicenseFileName, deprecated in 1.35, has been removed. Use MediaWiki\ExtensionInfo::getLicenseFileNames.


 * CategoryPage::getCategoryViewerClass and ::setCategoryViewerClass, deprecated in 1.35, have been removed.


 * SqlBlobStore::getLegacyEncodingConversionLang, deprecated in 1.34, has been removed.


 * wfCanIPUseHTTPS, deprecated in 1.37, has been removed.
 * wfGetScriptUrl, deprecated in 1.35, has been removed.
 * The following methods of Database class, are no longer stable to override:
 * ::implicitOrderby
 * ::selectSQLText
 * ::bitNot
 * ::bitAnd
 * ::bitOr
 * ::buildConcat
 * ::buildGreatest
 * ::buildLeast
 * ::buildSubstring
 * ::buildStringCast
 * ::buildIntegerCast
 * ::tableName
 * ::addIdentifierQuotes
 * ::buildLike
 * ::limitResult
 * ::unionSupportsOrderAndLimit
 * ::unionQueries
 * ::conditional
 * ::strreplace
 * ::timestamp
 * ::getInfinity
 * ::setTableAliases
 * ::setIndexAliases
 * ::buildGroupConcatField
 * SpecialUnblock::processUnblock, deprecated in 1.36, has been removed. Use UnblockUser instead.


 * wfLocalFile and wfFindFile, deprecated in 1.34, have been removed.
 * Maintenance script resetUserTokens.php, deprecated in 1.27, has been removed.
 * These methods in Database have been removed without deprecation as they are not used outside core. Users should override corresponding methods in SQLPlatform instead:


 * Database::doInsert -> SQLPlatform::insertSqlText
 * Database::doDropTable -> SQLPlatform::dropTableSqlText
 * Database::doRollback -> SQLPlatform::rollbackSqlText
 * Database::doSavepoint -> SQLPlatform::savepointSqlText
 * Database::doReleaseSavepoint -> SQLPlatform::releaseSavepointSqlText
 * Database::doRollbackToSavepoint -> SQLPlatform::rollbackToSavepointSqlText
 * The following protected methods of Database class have been removed without deprecation as they are not used outside core. Users should call corresponding methods in SQLPlatform:


 * Database::makeInsertLists -> SQLPlatform::makeInsertLists
 * Database::isFlagInOptions -> SQLPlatform::isFlagInOptions
 * Database::normalizeOptions -> SQLPlatform::normalizeOptions
 * Database::fieldNameWithAlias -> SQLPlatform::fieldNameWithAlias
 * Database::isTransactableQuery -> SQLPlatform::isTransactableQuery
 * $wgCanonicalNamespaceNames no longer includes custom namespaces defined using $wgExtraNamespaces. Extensions should use the NamespaceInfo service instead of accessing this configuration setting directly.


 * The following hook, deprecated in 1.35, has been removed:
 * ParserGetVariableValueVarCache: ParserGetVariableValueVarCacheHook
 * The $variableCache parameter to the ParserGetVariableValueSwitch hook is no longer used; non-standard use of this parameter has been deprecated since 1.35.


 * These methods have been moved from IDatabase to IMaintainableDatabase:
 * IDatabase::fieldExists -> IMaintainableDatabase::fieldExists
 * IDatabase::indexExists -> IMaintainableDatabase::indexExists
 * IDatabase::tableExists -> IMaintainableDatabase::tableExists
 * DBConnRef doesn't accept live connection in constructor anymore. Only parameters for getting connection should be provided.


 * IDatabase::getTopologyRootPrimary was removed.
 * User::blockedBy, deprecated since 1.38, has been removed.
 * User::getBlockId, deprecated since 1.38, has been removed.

Deprecations in 1.39
These methods are exact replacements except that moved to the MediaWiki\ResourceLoader namespace, the old names becoming deprecated aliases: DerivativeResourceLoaderContext, ResourceLoaderCircularDependencyError, ResourceLoaderClientHtml, ResourceLoaderCodexModule, ResourceLoaderContext, ResourceLoaderFileModule, ResourceLoaderFilePath, ResourceLoaderForeignApiModule, ResourceLoaderImage, ResourceLoaderImageModule, ResourceLoaderLanguageDataModule, ResourceLoaderLessVarFileModule, ResourceLoaderModule, ResourceLoaderMwUrlModule, ResourceLoaderOOUIFileModule, ResourceLoaderOOUIIconPackModule, ResourceLoaderOOUIImageModule, ResourceLoaderOOUIModule, ResourceLoaderSiteModule, ResourceLoaderSiteStylesModule, ResourceLoaderSkinModule, ResourceLoaderStartUpModule, ResourceLoaderUserModule, ResourceLoaderUserOptionsModule, ResourceLoaderUserStylesModule, ResourceLoaderWikiModule.
 * PageProps::getInstance, deprecated since 1.38, emits deprecations warnings.
 * The global function wfGetDB has been deprecated. Use LoadBalancer::getConnection instead.
 * SpecialRedirectWithAction::__construct without SearchEngineFactory argument is hard deprecated.
 * Use of the SiteStatsUpdate constructor has been deprecated in favor of the ::factory method.
 * AuthManager::checkAccountCreatePermissions has been deprecated. Use AuthManager::authorizeCreateAccount or AuthManager::probablyCanCreateAccount instead.
 * Title::getSelectFields has been deprecated in favor of PageStore::newSelectQueryBuilder
 * Title::newFromTitleValue, deprecated since in 1.34, now emits deprecation warnings. Use ::newFromLinkTarget instead.
 * ExtensionRegistry::readFromQueue has been marked @internal. Extensions should use ExtensionProcessor instead.
 * Processor::getExtraAutoloaderPaths and ExtensionProcessor::getExtraAutoloaderPaths have been deprecated, use get getExtractedAutoloadInfo instead.
 * The following global functions are deprecated in favor of the listed UrlUtils methods.
 * wfExpandUrl -> UrlUtils::expand
 * wfGetServerUrl -> UrlUtils::getServer
 * wfAssembleUrl -> UrlUtils::assemble
 * wfRemoveDotSegments -> UrlUtils::removeDotSegments
 * wfUrlProtocols -> UrlUtils::validProtocols
 * wfUrlProtocolsWithoutProtRel -> UrlUtils::validAbsoluteProtocols
 * wfParseUrl -> UrlUtils::parse
 * wfExpandIRI -> UrlUtils::expandIRI
 * wfMatchesDomainList -> UrlUtils::matchesDomainList
 * 1) they return null instead of false or empty string on error (where applicable);
 * 2) UrlUtils::validProtocols does not take a parameter (documentation said not to pass one to wfUrlProtocols anyway);
 * 3) they use type hints (don't try passing null instead of string, etc.).
 * MaintainableDBConnRef is deprecated, use DBConnRef instead.
 * Loading DefaultSettings.php is deprecated. To get default values of main config settings, use MainConfigSchema::listDefaultValues or MainConfigSchema::getDefaultValue.
 * AbstractContent::getRedirectChain and AbstractContent::getUltimateRedirectTarget are now emitting deprecation warnings (phab:T296430).
 * (phab:T244138) QueryPage::getSQL is deprecated. Instead QueryPage::getQueryInfo should be overridden.
 * Calling new JobRunner directly without $serviceOptions now emits deprecation warnings. Use MediaWikiServices::getInstance->getJobRunner instead.
 * Passing an array of targets to Article::getRedirectHeaderHtml is deprecated. Supply a single redirect target instead (phab:T296430).
 * The following Less mediawiki.mixins have been deprecated:
 * .animation
 * .animation-delay
 * .transform-rotate
 * Skin::getAction is deprecated. Use IContextSource::getActionName instead.
 * User::getOption, deprecated since 1.35, now emits deprecation warnings. Use UserOptionsLookup::getOption instead.
 * ILBFactory::forEachLB is deprecated. Use ::getAllLBs.
 * LoadBalancer::forEachOpenConnection and ::forEachOpenPrimaryConnection are deprecated without replacement.
 * The following classes were moved from the root namespace to the MediaWiki\ResourceLoader namespace, the old names becoming deprecated aliases: ResourceLoader, MessageBlobStore, VueComponentParser.
 * The following classes had the "ResourceLoader" prefix stripped while being
 * The following methods in WikiRevision and their interfaces ImportableUploadRevision and ImportableOldRevision are deprecated:
 * ::getUserObj → ::getUser
 * ::setUserObj → ::setUsername
 * ::setUserIP → ::setUsername
 * ObjectCache::addBusyCallback is deprecated and non-functional.
 * MWTimestamp::getHumanTimestamp, deprecated in 1.26, now emits deprecation warnings.
 * Article::viewRedirect, deprecated in 1.30, now emits deprecation warnings.
 * Parser::getFreshParser is deprecated, use ParserFactory::getInstance.
 * CoreParserFunctions::mwnamespace is deprecated and emits deprecation warnings, use CoreParserFunctions::namespace instead.
 * Registering magic variables whose names include a colon is deprecated.
 * User::blockedFor, deprecated in 1.35, now emits deprecation warnings.
 * Access to previously public properties AbstractBlock::$mExpiry, AbstractBlock::$mHideName, AbstractBlock::$mTimestamp, DatabaseBlock::$mAuto, and DatabaseBlock::$mParentBlockId, deprecated in 1.34, now emits deprecation warnings.
 * Access to previously public properties User::$mBlock, User::$mBlockedby, and User::$mHideName, deprecated in 1.35, now emits deprecation warnings.
 * JobQueueGroup::singleton and ::destroySingletons, deprecated in 1.37, now emit deprecation warnings.
 * Title::getNotificationTimestamp, deprecated in 1.35, now emits deprecation warnings.
 * Global functions wfReadOnly and wfReadOnlyReason, deprecated in 1.38, now emit deprecation warnings.
 * Overriding or calling DifferenceEngine::getDiffBodyCacheKey, deprecated in 1.31, now emits deprecation warnings.
 * Access to previously public property WikiRevision::$fileIsTemp, deprecated in 1.29, now emits deprecation warnings.
 * wfQueriesMustScale has been deprecated and emits deprecation warnings.
 * ContextSource::getStats, RequestContext::getStats, and DerivativeContext::getStats, deprecated in 1.27, now emit deprecation warnings.
 * ManualLogEntry::setTags, deprecated in 1.33, now emits deprecation warnings.
 * WikiRevision::downloadSource, deprecated in 1.31, now emits deprecation warnings.
 * DifferenceEngine::textDiff, deprecated in 1.32, now emits deprecation warnings.
 * FormatMetadata::flattenArrayContentLang, deprecated in 1.36, now emits deprecation warnings.
 * SkinTemplate::getNameSpaceKey, deprecated in 1.35, now emits deprecation warnings.
 * EnqueueJob::newFromJobsByWiki, deprecated in 1.33, now emits deprecation warnings.
 * The following methods of the MWGrants class, all deprecated since 1.38, are now emitting deprecation warnings:
 * getValidGrants
 * getRightsByGrant
 * grantName
 * grantNames
 * getGrantRights
 * grantsAreValid
 * getGrantGroups
 * getHiddenGrants
 * getGrantsLink
 * getGrantsWikiText
 * DataUpdate::runUpdates, deprecated in 1.28, now emits deprecation warnings.
 * CdnCacheUpdate::newFromTitles, deprecated in 1.35, now emits deprecation warnings.
 * Instantiating HTMLCacheUpdate class, deprecated in 1.34, now emits deprecation warnings.
 * ISQLPlatform::tableNames (implemented by IDatabase) is soft deprecated. None of the tableName* functions should be used by most users; if you absolutely must use raw SQL, write several tableName calls instead.
 * Language::isWellFormedLanguageTag has been deprecated in favor of LanguageCode::isWellFormedLanguageTag.
 * The PrevNextNavigationRenderer helper class has been deprecated in favor of the new PagerNavigationBuilder one.
 * The methods IndexPager::getPagingLinks, IndexPager::getLimitLinks and IndexPager::buildPrevNextNavigation have been deprecated in favor of IndexPager::getNavigationBuilder.
 * Overriding the method IndexPager::makeLink has been deprecated.

Other changes in 1.39

 * Dynamic default values are now applied before extension registration callbacks are run. This way, extensions have a complete view of config variables, with all defaults applied. For example, when the default value of X used to be static but becomes dynamic, and an extension reads the value of X in the registration callback, it will now continue to function as expected. In some cases however, this may cause an undesired change in behavior: if the dynamic default of setting X depends on the value of setting Y, and an extension changes Y, the changed value of Y will no longer affect the value of X.

Compatibility
MediaWiki 1.39 requires PHP 7.4.3 or later and the following PHP extensions:


 * ctype
 * dom
 * fileinfo
 * iconv
 * intl
 * json
 * mbstring
 * xml

MariaDB is the recommended database software. MySQL, PostgreSQL, or SQLite can be used instead, but support for them is somewhat less mature.

The supported versions are:


 * MariaDB 10.3 or higher
 * MySQL 5.7.0 or higher
 * PostgreSQL 10 or later
 * SQLite 3.8.0 or later

Online documentation
Documentation for both end-users and site administrators is available on MediaWiki.org, and is covered under the GNU Free Documentation License (except for pages that explicitly state that their contents are in the public domain):



Mailing list
A mailing list is available for MediaWiki user support and discussion:



A low-traffic announcements-only list is also available:



It's highly recommended that you sign up for one of these lists if you're going to run a public MediaWiki, so you can be notified of security fixes.

IRC help
There's usually someone online in #mediawiki on irc.libera.chat.