RELEASE-NOTES-1.31

   1 == MediaWiki 1.31 ==
   2
   3 THIS IS NOT A RELEASE YET
   4
   5 MediaWiki 1.31 is an alpha-quality branch and is not recommended for use in
   6 production.
   7
   8 === Important pre-upgrade notes for 1.31 ===
   9 * If you're using MySQL, SQLite, or MSSQL, are not using update.php to apply
  10   schema changes, and cannot have downtime to run migrateArchiveText.php and
  11   apply patch-drop-ar_text.sql manually, you'll have to apply a default value
  12   to the ar_text and ar_flags columns of the archive table or make those
  13   columns nullable before upgrading to MediaWiki 1.31.
  14   maintenance/archives/patch-nullable-ar_text.sql shows how to do this for MySQL.
  15
  16 === Configuration changes in 1.31 ===
  17 * $wgEnableAPI and $wgEnableWriteAPI are now deprecated and will be removed in
  18   a future version. The API is now considered to be stable, secure and
  19   essential.
  20 * $wgUsejQueryThree was removed, as it is now the default. This was documented
  21   as a temporary variable during the migration period, deprecated since 1.29.
  22 * $wgLogoHD has been updated to support svg images and uses $wgLogo where
  23   possible for fallback images such as png.
  24 * (T44246) $wgFilterLogTypes will no longer ignore 'patrol' when user does not
  25   have the right to mark things patrolled.
  26 * Wikis that contain imported revisions or CentralAuth global blocks should run
  27   maintenance/cleanupUsersWithNoId.php.
  28 * The configuration settings $wgResourceLoaderMinifierStatementsOnOwnLine and
  29   $wgResourceLoaderMinifierMaxLineLength, deprecated since 1.27, were removed.
  30 * (T180921) $wgReferrerPolicy now supports having fallbacks for browsers that
  31   are not using the latest version of the Referrer Policy specification.
  32 * $wgFragmentMode is now set to [ 'legacy', 'html5' ] by default. This is a
  33   first step of migration to human-readable section IDs that will later result
  34   in 'html5' being the default mode.
  35 * CACHE_ACCEL now only supports APC(u) or WinCache. XCache support was removed
  36   as upstream is inactive and has no plans to move to PHP 7.
  37 * The old CategorizedRecentChanges feature, including its related configuration
  38   option $wgAllowCategorizedRecentChanges, has been removed.
  39 * (T188472) The 'comma' value for $wgArticleCountMethod is no longer supported
  40   for performance reasons, and installations with this setting will now work as
  41   if it was configured with 'any'.
  42 * (T185753) MediaWiki now defaults to using RemexHtml to tidy up user input,
  43   rather than being off by default. If you wish to disable HTML tidying
  44   entirely, set $wgTidyConfig to null; if you wish to use the old, deprecated
  45   Tidy external binary, both set $wgTidyConfig to null and $wgUseTidy to true.
  46 * $wgLogAutopatrol now defaults to false instead of true.
  47 * $wgValidateAllHtml was removed and will be ignored.
  48 * $wgScriptExtension, deprecated and ignored since 1.25, was removed. See the
  49   1.25 release notes for more information.
  50 * $wgUseAjax is now marked as deprecated, just like the deprecated AJAX
  51   framework that it enables. Some extensions mistakenly used this to check
  52   whether any AJAX functionality at all should be enabled, further making this
  53   problematic to retain.
  54 * Add default edit rate limit of 90 edits/minute for all users.
  55 * $wgDBmysql5 is now deprecated, and will be removed in a future version. It
  56   has been marked as experimental ever since it was introduced.
  57
  58 === New features in 1.31 ===
  59 * (T76554) User sub-pages named ….json are now protected in the same way that
  60   ….js and ….css pages are, so that configuration options can safely be placed
  61   there.
  62 * Wikimedia\Rdbms\IDatabase->select() and similar methods now support joins
  63   with parentheses for grouping.
  64 * As a first pass in standardizing dialog boxes across the MediaWiki product,
  65   Html class now provides helper methods for messageBox, successBox, errorBox
  66   and warningBox generation.
  67 * (T9240) Imports will now record unknown (and, optionally, known) usernames in
  68   a format like "iw>Example".
  69 * (T20209) Linker (used on history pages, log pages, and so on) will display
  70   usernames formed like "iw>Example" as interwiki links, as if by wikitext like
  71   [[iw:User:Example|iw>Example]].
  72 * (T111605) The 'ImportHandleUnknownUser' hook allows extensions to auto-create
  73   users during an import.
  74 * Added a hook, ParserOutputPostCacheTransform, to allow extensions to affect
  75   the ParserOutput::getText() post-cache transformations.
  76 * Added a hook, UploadForm:getInitialPageText, to allow extensions to alter the
  77   initial page text for file uploads.
  78 * (T181651) The info page for File pages now displays the file's base-16 SHA1
  79   hash value in the table of basic information.
  80 * Style tags with a 'data-mw-deduplicate' attribute will be deduplicated as a
  81   ParserOutput::getText() post-cache transformation. This may be disabled by
  82   passing 'deduplicateStyles' => false to that method.
  83 * The identity of the logged-in or IP "actor" for logged actions is being moved
  84   into a new actor table, with the rows in tables such as revision and logging
  85   referring to the actor ID instead of storing the user ID and name/IP in
  86   every row.
  87   * This is currently gated by $wgActorTableSchemaMigrationStage. Most wikis
  88     can set this to MIGRATION_NEW and run maintenance/migrateActors.php as
  89     soon as any necessary extensions are updated.
  90   * Most code accessing rows for logged actions from the database should use
  91     the relevant getQueryInfo() methods to get the information needed to build
  92     the SQL query. The ActorMigration class may also be used to get feature
  93     -flagged information needed to access actor-related fields during the
  94     migration period.
  95 * Added Wikimedia\Rdbms\IDatabase::cancelAtomic(), to roll back an atomic
  96   section without having to roll back the whole transaction.
  97 * Wikimedia\Rdbms\IDatabase::doAtomicSection(), non-native ::insertSelect(),
  98   and non-MySQL ::replace() and ::upsert() no longer roll back the whole
  99   transaction on failure.
 100 * (T189785) Added a monthly heartbeat ping to the pingback feature.
 101 * The CLI installer (maintenance/install.php) learned to detect and include
 102   extensions. Pass --with-extensions to enable that feature.
 103 * (T184791) rc_patrolled now has three states: "0" for unpatrolled,
 104   "1" for manually patrolled and "2" for autopatrolled actions.
 105 * Extensions can now set their type to "editor" if they provide an editor or
 106   enhance the editing experience.
 107 * Extensions can use a PSR-4 autoloader by setting an "AutoloadNamespaces"
 108   property in extension.json. See the documentation at
 109   <https://mediawiki.org/wiki/Manual:Extension.json/Schema#AutoloadNamespaces>
 110   for more details and an example.
 111 * (T19099) Tabs which link to pages that don't exist (like those to uncreated
 112   discussion pages) now have a tooltip to indicate state, not just colour.
 113
 114 === External library changes in 1.31 ===
 115 * pear/mail, pear/mail_mime and pear/mail_mime-decode have been moved from
 116   suggested to required. These packages now must be installed via composer
 117   and not via PEAR itself.
 118
 119 ==== Upgraded external libraries ====
 120 * Updated jquery.chosen from v0.9.14 to v1.8.2.
 121 * Updated composer/spdx-licenses from 1.1.4 to 1.3.0 (development dependency).
 122 * Updated nikic/php-parser from 2.1.0 to 3.1.3 (development dependency).
 123 * Updated wikimedia/ip-set from 1.1.0 to 1.2.0.
 124 * Updated wikimedia/relpath from 2.0.0 to 2.1.1.
 125 * Updated wikimedia/running-stat from 1.1.0 to 1.2.0.
 126 * Updated wikimedia/wrappedstring from 2.2.0 to 2.3.0.
 127 * Updated mediawiki/at-ease from 1.1.0 to 1.2.0.
 128 * Updated wikimedia/php-session-serializer from 1.0.4 to 1.0.6.
 129 * Updated wikimedia/remex-html from 1.0.2 to 1.0.3.
 130 * Updated wikimedia/html-formatter from 1.0.1 to 1.0.2.
 131
 132 ==== New external libraries ====
 133 * Added wikimedia/object-factory 1.0.0
 134
 135 ==== Removed and replaced external libraries ====
 136 * (T17845) The deprecated 'jquery.badge' module was removed.
 137 * The deprecated 'jquery.autoEllipsis' module was removed. Use the CSS
 138   text-overflow property instead.
 139 * The deprecated 'jquery.placeholder' module was removed.
 140 * The deprecated 'jquery.appear' module was removed. Use the
 141   'mediawiki.viewport' module instead.
 142 * mediawiki/at-ease was replaced with wikimedia/at-ease.
 143
 144 === Bug fixes in 1.31 ===
 145 * (T90902) Non-breaking space in header ID breaks anchor.
 146 * (T189375) CSSMin now allows quoted urls in `url()` syntax to start with a
 147   space.
 148 * (T2087, T10897, T87753, T174639) Whitespace created by category and language
 149   links is now stripped rather than leaving blank lines in odd places.
 150 * (T3780) Uploads with UTF-8 names now work on PHP7.1+ on Windows servers.
 151 * (T186565) Fix PHP Notice from `ob_end_flush()` in `FileRepo::streamFile()`.
 152
 153 === Action API changes in 1.31 ===
 154 * (T185058) The 'name' value to tgprop for action=query&list=tags has been
 155   removed. It has never made a difference in the output, the name was always
 156   returned regardless.
 157 * The 'watch' and 'unwatch' parameters for action=move have been removed. They
 158   were deprecated and also accidentally nonfunctional since 1.17 in 2010. Use
 159   'watchlist' instead.
 160
 161 === Action API internal changes in 1.31 ===
 162 * ApiBase::getProfileDBTime, deprecated since 1.25, was removed.
 163 * ApiBase::getModuleProfileName, deprecated since 1.25, was removed.
 164 * ApiBase::getProfileTime, deprecated since 1.25, was removed.
 165
 166 === Languages updated in 1.31 ===
 167 MediaWiki supports over 350 languages. Many localisations are updated
 168 regularly. Below only new and removed languages are listed, as well as
 169 changes to languages because of Phabricator reports.
 170
 171 * (T180052) Mirandese (mwl) now supports gendered NS_USER/NS_USER_TALK.
 172 * (T182305) New language support: Nyungar (nys).
 173 * (T186359) New language support: Siberian Tatar [cебертатар] (sty).
 174 * (T186635) New language support: Guianan Creole (gcr).
 175 * (T186647) New language support: Kumyk [къумукъ] (kum).
 176 * (T187750) New language support: Spanish formal address (es-formal).
 177 * (T187824) New language support: Hungarian formal address (hu-formal).
 178 * (T189127) New language support: Gorontalo (gor).
 179
 180 === Breaking changes in 1.31 ===
 181 * MessageBlobStore::insertMessageBlob(), deprecated in 1.27, was removed.
 182 * The OutputPage class constructor now requires a context parameter.
 183   Instantiating without context was deprecated in 1.18.
 184 * The mw.page JavaScript singleton, deprecated in 1.30, was removed.
 185 * Article::getLastPurgeTimestamp(), WikiPage::getLastPurgeTimestamp(), and the
 186   related WikiPage::PURGE_* constants, deprecated in 1.29, were removed.
 187 * The Article::selectFields(), ::onArticleCreate(), ::onArticleDelete(), and
 188   ::onArticleEdit() methods, deprecated in 1.24, were removed.
 189 * Installer::locateExecutable() and ::locateExecutableInDefaultPaths() were
 190   removed. Use ExecutableFinder::findInDefaultPaths() instead.
 191 * The deprecated MW_DIFF_VERSION constant was removed.
 192   DifferenceEngine::MW_DIFF_VERSION should be used instead.
 193 * Due to significant refactoring, method ContribsPager::getUserCond() that had
 194   no access restriction has been removed.
 195 * The Block class will no longer accept usable-but-missing usernames for
 196   'byText' or ->setBlocker(). Callers should either ensure the blocker exists
 197   locally or use a new interwiki-format username like "iw>Example".
 198 * The following methods and constants from the WatchedItem class, which were
 199   deprecated in 1.27, have been removed:
 200   * WatchedItem::getTitle()
 201   * WatchedItem::fromUserTitle()
 202   * WatchedItem::addWatch()
 203   * WatchedItem::removeWatch()
 204   * WatchedItem::isWatched()
 205   * WatchedItem::duplicateEntries()
 206   * WatchedItem::IGNORE_USER_RIGHTS
 207   * WatchedItem::CHECK_USER_RIGHTS
 208   * WatchedItem::DEPRECATED_USAGE_TIMESTAMP
 209 * The $statementsOnOwnLine parameter of JavaScriptMinifier::minify was removed.
 210   $wgResourceLoaderMinifierStatementsOnOwnLine, the corresponding configuration
 211   variable, has been deprecated since 1.27 and was removed as well.
 212 * The $maxLineLength parameter of JavaScriptMinifier::minify was removed.
 213   $wgResourceLoaderMinifierMaxLineLength, the corresponding configuration
 214   variable, has been deprecated since 1.27 and was removed as well.
 215 * The HtmlFormatter class, deprecated in 1.27, was removed. The namespaced
 216   HtmlFormatter\HtmlFormatter class should be used instead.
 217 * The driver 'mysql' for MySQL, deprecated in MediaWiki 1.30, has been removed.
 218   The driver has been deprecated since PHP 5.5 and was removed in PHP 7.0. The
 219   default driver for MySQL has been 'mysqli' since MediaWiki 1.22.
 220 * The following properties of PreparedEdit were deprecated in 1.21 and have
 221   been removed:
 222   * PreparedEdit->newText
 223   * PreparedEdit->oldText
 224   * PreparedEdit->pst
 225 * ParserOutput objects which are generated using a non-default value for
 226   ParserOptions::setWrapOutputClass() can no longer be added to the parser
 227   cache.
 228 * The following deprecated methods from the OutputPage class have been removed:
 229   * OutputPage::addExtensionStyle(); deprecated in 1.27
 230   * OutputPage::getExtStyle(); deprecated in 1.27
 231   * OutputPage::setETag(); deprecated in 1.28 (obsolete no-op)
 232   * OutputPage::setSquidMaxage(); deprecated in 1.27
 233   * OutputPage::readOnlyPage(); deprecated in 1.25
 234   * OutputPage::rateLimited(); deprecated in 1.25
 235   * Additionally, the protected OutputPage::$mExtStyles array, only accessed
 236     through the above and with no known uses, was removed.
 237 * The no-op method Skin::showIPinHeader(), deprecated in 1.27, was removed.
 238 * The following variables and methods in EditPage, deprecated in MediaWiki 1.30,
 239   were removed:
 240   * $isCssJsSubpage — use ::isUserConfigPage()
 241   * $isCssSubpage — use ::isUserCssConfigPage()
 242   * $isJsSubpage — use ::isUserJsConfigPage()
 243   * $isWrongCaseCssJsPage – use ::isWrongCaseUserConfigPage()
 244   * ::getSummaryInput() – use ::getSummaryInputWidget()
 245   * ::getSummaryInputOOUI() – use ::getSummaryInputWidget()
 246   * ::getCheckboxes() – use ::getCheckboxesWidget() or
 247       ::getCheckboxesDefinition()
 248   * ::getCheckboxesOOUI() – use ::getCheckboxesWidget() or
 249       ::getCheckboxesDefinition()
 250 * ResourceLoaderModule::getPosition(), deprecated in 1.29, has been removed.
 251 * In User, the cookie-related methods which were wrappers for the functions on
 252   the response object, and were deprecated in 1.27, have been removed:
 253   * ::setCookie()
 254   * ::clearCookie()
 255   * ::setExtendedLoginCookie()
 256   Note that User::setCookies() remains, and is not deprecated.
 257 * Also in User, some auth-related methods which were deprecated in 1.27 have
 258   been removed:
 259   * ::getEditTokenTimestamp() – use MediaWiki\Session\Token::getTimestamp()
 260   * ::getPasswordFactory() – create a PasswordFactory directly
 261   * ::passwordChangeInputAttribs()
 262 * The global functions wfProfileIn and wfProfileOut, deprecated in 1.25, have
 263   been removed.
 264 * SpecialPageFactory::getList(), deprecated in 1.24, has been removed. You can
 265   use ::getNames() instead.
 266 * OpenSearch::getOpenSearchTemplate(), deprecated in 1.25, has been removed. You
 267   can use ApiOpenSearch::getOpenSearchTemplate() instead.
 268 * The global function wfBaseConvert, deprecated in 1.27, has been removed. Use
 269   Wikimedia\base_convert() directly.
 270 * Calling Database::begin() explicitly during an implicit transaction or when
 271   DBO_TRX is set results in an exception. Calling Database::commit() explicitly
 272   for an implicit transaction also results in an exception. Previously these
 273   were logged as errors. The startAtomic() and endAtomic() methods, or
 274   AtomicSectionUpdate should be used instead.
 275 * The global function wfOutputHandler() was removed, use the its replacement
 276   MediaWiki\OutputHandler::handle() instead. The global function was only
 277   sometimes defined. Its replacement is always available via the autoloader.
 278 * ChangeTags::listExtensionActivatedTags and ::listExtensionDefinedTags,
 279   deprecated in 1.28, have been removed. Use ::listSoftwareActivatedTags() and
 280   ::listSoftwareDefinedTags() instead.
 281 * Title::getTitleInvalidRegex(), deprecated in 1.25, has been removed. You can
 282   use MediaWikiTitleCodec::getTitleInvalidRegex() instead.
 283 * HTMLForm & VFormHTMLForm::isVForm(), deprecated in 1.25, have been removed.
 284 * The ProfileSection class, deprecated in 1.25 and unused, has been removed.
 285 * The ResourceLoaderGetLessVars hook, deprecated in 1.30, has been removed. Use
 286   ResourceLoaderModule::getLessVars() to expose local variables instead of
 287   global ones.
 288 * As part of work to modernise user-generated content clean-up, a config option
 289   and some methods related to HTML validity were removed without deprecation.
 290   The public methods MWTidy::checkErrors() and the path through which it was
 291   called, TidyDriverBase::validate(), are removed, as are the testing methods
 292   MediaWikiTestCase::assertValidHtmlSnippet() and ::assertValidHtmlDocument().
 293   The $wgValidateAllHtml configuration option is removed and will be ignored.
 294 * Execution of external programs using MediaWiki\Shell\Command now applies
 295   the RESTRICT_DEFAULT Firejail restriction by default.
 296 * The ResourceLoaderModule::getHashMtime() and ::getDefinitionMtime() methods,
 297   deprecated in 1.26, were removed.
 298 * The deprecated 'mediawiki.widgets.CategorySelector' module alias was removed.
 299   Use the 'mediawiki.widgets.CategoryMultiselectWidget' module directly.
 300
 301 === Deprecations in 1.31 ===
 302 * The Revision class was deprecated in favor of RevisionStore, BlobStore, and
 303   RevisionRecord and its subclasses.
 304 * The global function wfBCP47 is deprecated in favour of LanguageCode::bcp47.
 305 * The global function wfCountDown is now deprecated in favor of
 306   Maintenance::countDown.
 307 * Several methods for returning lists of fields to select from the database
 308   have been deprecated in favor of similar methods that also return the tables
 309   to select from and the join conditions for those tables.
 310   * Block::selectFields() → Block::getQueryInfo()
 311   * RecentChange::selectFields() → RecentChange::getQueryInfo()
 312   * ArchivedFile::selectFields() → ArchivedFile::getQueryInfo()
 313   * LocalFile::selectFields() → LocalFile::getQueryInfo()
 314   * LocalFile::getCacheFields() with a prefix no longer works
 315   * LocalFile::getLazyCacheFields() with a prefix no longer works
 316   * OldLocalFile::selectFields() → OldLocalFile::getQueryInfo()
 317   * RecentChange::selectFields() → RecentChange::getQueryInfo()
 318   * Revision::userJoinCond() → Revision::getQueryInfo( [ 'user' ] )
 319   * Revision::selectUserFields() → Revision::getQueryInfo( [ 'user' ] )
 320   * Revision::pageJoinCond() → Revision::getQueryInfo( [ 'page' ] )
 321   * Revision::selectPageFields() → Revision::getQueryInfo( [ 'page' ] )
 322   * Revision::selectTextFields() → Revision::getQueryInfo( [ 'text' ] )
 323   * Revision::selectFields() → Revision::getQueryInfo()
 324   * Revision::selectArchiveFields() → Revision::getArchiveQueryInfo()
 325   * User::selectFields() → User::getQueryInfo()
 326   * WikiPage::selectFields() → WikiPage::getQueryInfo()
 327 * Revision::setUserIdAndName() was deprecated.
 328 * Access to TitleValue class properties was deprecated, the relevant getters
 329   should be used instead.
 330 * DifferenceEngine::getDiffBodyCacheKey() is deprecated. Subclasses should
 331   override DifferenceEngine::getDiffBodyCacheKeyParams() instead.
 332 * Use of Maintenance::error( $err, $die ) to exit script was deprecated. Use
 333   Maintenance::fatalError() instead.
 334 * Passing a ParserOptions object to OutputPage::parserOptions() is deprecated.
 335 * The RevisionInsertComplete hook is now deprecated; use instead the hook
 336   RevisionRecordInserted. RevisionInsertComplete is still called, but the second
 337   and third parameter will always be null. Hard deprecation is scheduled for 1.32.
 338 * The following methods that get and set ParserOutput state are deprecated.
 339   Callers should use the new stateless $options parameter to
 340   ParserOutput::getText() instead.
 341   * ParserOptions::getEditSection()
 342   * ParserOptions::setEditSection()
 343   * ParserOutput::getEditSectionTokens()
 344   * ParserOutput::setEditSectionTokens()
 345   * ParserOutput::getTOCEnabled()
 346   * ParserOutput::setTOCEnabled()
 347   * OutputPage::enableSectionEditLinks()
 348   * OutputPage::sectionEditLinksEnabled()
 349   * The public ParserOutput state fields $mTOCEnabled and $mEditSectionTokens
 350     are also deprecated.
 351 * License::getLicenses has been deprecated; use License::getLines instead.
 352 * QuickTemplate::setRef() was deprecated in favour of QuickTemplate::set().
 353   Setting template variables by reference allowed violating the principle of
 354   data being immutable once added to the skin template. In practice, this method
 355   was not being used for that. Rather, setRef() existed as memory optimisation
 356   for PHP 4.
 357 * QuickTemplate::setTranslator() and MediaWikiI18N::set() were deprecated in
 358   favour of Skin::msg() parameters.
 359 * MediaWikiI18N::translate() was deprecated in favour of Skin::msg() or
 360   wfMessage().
 361 * Passing false to ParserOptions::setWrapOutputClass() is deprecated. Use the
 362   'unwrap' transform to ParserOutput::getText() instead.
 363 * \ObjectFactory (no namespace) is deprecated, the namespaced class
 364   \Wikimedia\ObjectFactory from the wikimedia/object-factory library should be
 365   used instead.
 366 * CommentStore::newKey is deprecated. Instead, get an instance from
 367   MediaWikiServices.
 368 * The following CommentStore methods have had their signatures changed to
 369   introduce a $key parameter, usage of the methods on instances retrieved from
 370   CommentStore::newKey will remain unchanged but deprecated:
 371   * CommentStore::getFields
 372   * CommentStore::getJoin
 373   * CommentStore::getComment
 374   * CommentStore::getCommentLegacy
 375   * CommentStore::insert
 376   * CommentStore::insertWithTemplate
 377 * The following methods in Title have been renamed, and the old ones are
 378   deprecated:
 379   * Title::getSkinFromCssJsSubpage – use ::getSkinFromConfigSubpage
 380   * Title::isCssOrJsPage – use ::isSiteConfigPage
 381   * Title::isCssJsSubpage – use ::isUserConfigPage
 382   * Title::isCssSubpage – use ::isUserCssConfigPage
 383   * Title::isJsSubpage – use ::isUserJsConfigPage
 384 * The following methods related to caching of half-parsed HTML were deprecated:
 385   * Parser::serializeHalfParsedText()
 386   * Parser::unserializeHalfParsedText()
 387   * Parser::isValidHalfParsedText()
 388   * StripState::getSubState()
 389   * StripState::merge()
 390 * The DeferredStringifier class is deprecated, use Message::listParam() instead.
 391 * The type string for the parameter $lang of DateFormatter::getInstance is
 392   deprecated.
 393 * Wikimedia\Rdbms\SavepointPostgres is deprecated.
 394 * The DO_MAINTENANCE constant is deprecated. RUN_MAINTENANCE_IF_MAIN should be
 395   used instead.
 396 * The function wfShellWikiCmd() has been deprecated, use
 397   MediaWiki\Shell::makeScriptCommand().
 398 * In the future, the hooks 'PreferencesFormPreSave' and 'PreferencesGetLegend'
 399   will be allowed to provide any HTMLForm object rather than PreferencesForm.
 400
 401 === Other changes in 1.31 ===
 402 * Browser support for Internet Explorer 10 was lowered from Grade A to Grade C.
 403 * Browser support for Opera 12 and older was dropped entirely. Opera 15+
 404   continues at Grade A.
 405 * Multi-content-revision capability was introduced into the storage layer. See
 406   <https://mediawiki.org/wiki/Requests_for_comment/Multi-Content_Revisions>.
 407 * The "free" CSS class is now only applied to unbracketed URLs in wikitext.
 408   Links written using square brackets will get the class "text" not "free".
 409 * RFC 157418: Whitespace is trimmed from wikitext headings, wikitext list items,
 410   wikitext table captions, wikitext table headings, wikitext table cells. HTML
 411   headings, HTML list items, HTML table captions, HTML table headings, HTML
 412   table cells will not have this trimming behavior.
 413
 414 == Compatibility ==
 415 MediaWiki 1.31 requires PHP 7.0.0 or later. Although HHVM 3.18.5 or later is
 416 supported, it is generally advised to use PHP 7.0.0 or later for long term
 417 support.
 418
 419 MySQL/MariaDB is the recommended DBMS. PostgreSQL or SQLite can also be used,
 420 but support for them is somewhat less mature. There is experimental support for
 421 Oracle and Microsoft SQL Server.
 422
 423 The supported versions are:
 424
 425 * MySQL 5.5.8 or later
 426 * PostgreSQL 9.2 or later
 427 * SQLite 3.3.7 or later
 428 * Oracle 9.0.1 or later
 429 * Microsoft SQL Server 2005 (9.00.1399)
 430
 431 == Upgrading ==
 432 1.31 has several database changes since 1.30, and will not work without schema
 433 updates. Note that due to changes to some very large tables like the revision
 434 table, the schema update may take quite long (minutes on a medium sized site,
 435 many hours on a large site).
 436
 437 Don't forget to always back up your database before upgrading!
 438
 439 See the file UPGRADE for more detailed upgrade instructions, including
 440 important information when upgrading from versions prior to 1.11.
 441
 442 For notes on 1.30.x and older releases, see HISTORY.
 443
 444 == Online documentation ==
 445 Documentation for both end-users and site administrators is available on
 446 MediaWiki.org, and is covered under the GNU Free Documentation License (except
 447 for pages that explicitly state that their contents are in the public domain):
 448
 449        https://www.mediawiki.org/wiki/Special:MyLanguage/Documentation
 450
 451 == Mailing list ==
 452 A mailing list is available for MediaWiki user support and discussion:
 453
 454        https://lists.wikimedia.org/mailman/listinfo/mediawiki-l
 455
 456 A low-traffic announcements-only list is also available:
 457
 458        https://lists.wikimedia.org/mailman/listinfo/mediawiki-announce
 459
 460 It's highly recommended that you sign up for one of these lists if you're
 461 going to run a public MediaWiki, so you can be notified of security fixes.
 462
 463 == IRC help ==
 464 There's usually someone online in #mediawiki on irc.freenode.net.