Manual:Hooks

For hooks in the JS library of MediaWiki, see: mw.hook.

Hooks allow custom code to be executed when some defined event (such as saving a page or a user logging in) occurs. For example, the following code snippet will trigger a call to the function MyExtensionHooks::onPageContentSaveComplete whenever the PageContentSaveComplete hook runs, passing it function arguments specific to PageContentSaveComplete .

Hooks can be registered by mapping the name of the hook to the callback in the extension's extension.json file:

"Hooks": {
    "PageContentSaveComplete": "MyExtensionHooks::onPageContentSaveComplete",
    "MyCustomHook": "MyExtensionHooks::myCustomHook"
}

MediaWiki provides many hooks like this to extend the functionality of the MediaWiki software. Assigning a function (known as an event handler) to a hook will cause that function to be called at the appropriate point in the main MediaWiki code, to perform whatever additional task(s) the developer thinks would be useful at that point. Each hook can have multiple handlers assigned to it, in which case it will call the functions in the order that they are assigned, with any modifications made by one function passed on to subsequent functions in the chain.

Assign functions to hooks at the end of LocalSettings.php or in your own extension file at the file scope (not in a $wgExtensionFunctions function or the ParserFirstCallInit hook). For extensions, if the hook function's behavior is conditioned on a setting in LocalSettings.php, the hook should be assigned and the function should terminate early if the condition was not met.

You can also create new hooks in your own extension. It is registered in extension.json the same way as if you were registering a built-in MediaWiki hook to use in your extension. You can then run your hook within your extension by calling Hooks::run( 'HookName', [ $param1, $param2 ] );. Lastly, don't forget to add them to Category:Extension hooks .

Background

A hook is triggered by a call to HookContainer::run, usually via a method in HookRunner. HookContainer will find the hook handlers to run and call them with the parameters given to HookContainer::run. Hook handlers are registered via extension.json .

See also Hooks.md.

In this example from the doPurge function in WikiPage.php, doPurge calls HookRunner::onArticlePurge to run the ArticlePurge hook, passing $this as argument:

$this->getHookRunner()->onArticlePurge( $this )

The Core calls many hooks, but Extensions can also call hooks.

Writing an event handler

An event handler is a function you assign to a hook, which will be run whenever the event represented by that hook occurs. It consists of:

• a function with some optional accompanying data, or
• an object with a method and some optional accompanying data.

Register the event handler by adding it to the global $wgHooks array for a given event. Hooks can be added from any point in the execution before the hook is called, but are most commonly added in LocalSettings.php, its included files, or, for extensions, in the file extension.json. All the following are valid ways to define a hook function for the event EventName that is passed two parameters, showing the code that will be executed when EventName happens:

Format	Syntax	Resulting function call.
Static function	$wgHooks['EventName'][] = 'MyExtensionHooks::onEventName';	MyExtensionHooks::onEventName( $param1, $param2 );
Function, no data	$wgHooks['EventName'][] = 'someFunction';	someFunction( $param1, $param2 );
Function with data	$wgHooks['EventName'][] = [ 'someFunction', $someData ];	someFunction( $someData, $param1, $param2 );
Function, no data (weird syntax, but OK)	$wgHooks['EventName'][] = [ 'someFunction' ];	someFunction( $param1, $param2 );
inline anonymous function	$wgHooks['EventName'][] = function ( $param1, $param2 ) { // ...function body };	(the anonymous function is called with the hook's parameters)
Object only	$wgHooks['EventName'][] = $object;	$object->onEventName( $param1, $param2 );
Object with method	$wgHooks['EventName'][] = [ $object, 'someMethod' ];	$object->someMethod( $param1, $param2 );
Object with method and data	$wgHooks['EventName'][] = [ $object, 'someMethod', $someData ];	$object->someMethod( $someData, $param1, $param2 );
Object only (weird syntax, but OK)	$wgHooks['EventName'][] = [ $object ];	$object->onEventName( $param1, $param2 );

For extensions, the syntax is similar in the file extension.json (corresponding to the first and second case above):

{
	"Hooks": {
		"EventName": [
			"MyExtensionHooks::onEventName",
			"someFunction"
		]
	}
}

When an event occurs, the function (or object method) that you registered will be called, the event's parameters, along with any optional data you provided at registration. Note that when an object is the hook and you didn't specify a method, the method called is "onEventName". For other events this would be 'onArticleSave', 'onUserLogin', etc.

The optional data is useful if you want to use the same function or object for different purposes. For example:

$wgHooks['PageContentSaveComplete'][] = [ 'ircNotify', 'TimStarling' ];
$wgHooks['PageContentSaveComplete'][] = [ 'ircNotify', 'brion' ];

This code would result in ircNotify being run twice when a page is saved: once for 'TimStarling', and once for 'brion'.

Event handlers can return one of three possible values:

• no return value (or null): the hook handler has operated successfully. (Before MediaWiki 1.23, returning true was required.)
• "some string": an error occurred; processing should stop and the error should be shown to the user
• false: the hook handler has done all the work necessary, or replaced normal handling. This will prevent further handlers from being run, and in some cases tells the calling function to skip normal processing.

In many cases where an error message is expected, the hook will define a variable passed as a reference for extensions to store an error message and this is preferred over returning a string that will simply be displayed as an "internal error."

Returning false makes less sense for events where the action is complete, and will normally be ignored by the caller.

Handling hooks in MediaWiki 1.35 and later

MediaWiki version:

≥ 1.35

MediaWiki 1.35 introduces a system for handling hooks based on individual hook interfaces. This system allows for dependency injection, provides machine-readable parameter names and types, and integrates hook documentation with code editors.

For extensions, methods of registering and handling hooks in MediaWiki 1.34 and earlier are not being deprecated and will continue to work as expected. Extension authors who want to pilot the new system are welcome to do so. To learn more, see the hook specification in MediaWiki Core and the announcement on wikitech-l.

Changes to hook names

Prior to MediaWiki 1.35, several hooks included colons in their names. With the implementation of hook interfaces, colons in hook names have been replaced with underscores. For example, the interface for ApiFeedContributions::feedItem is ApiFeedContributions__feedItemHook. This does not impact extensions using the hook system in MediaWiki 1.34 and earlier.

Registering hooks using HookHandlers

To register a hook in an extension's extension.json file, the new system uses HookHandlers to specify how the handler object is created. Instead of mapping a hook directly to a function, a hook maps to a HookHandlers object which specifies the class and has the option to inject services.

For example, to register the BeforePageDisplay hook:

{
    "Hooks": {
        "BeforePageDisplay": "main"
    },
    "HookHandlers": {
        "main": {
            "class": "MediaWiki\\Extension\\MyExtension\\HookHandler",
            "services": [ "UserNameUtils" ]
        }
    }
}

Handling hooks using interfaces

To work with registration using HookHandlers, extensions should define an event handler class that implements the hook interface. Hook interfaces are named with the hook name with "Hook" appended.

namespace MediaWiki\Extension\MyExtension;

use OutputPage;
use Skin;

class HookHandler implements BeforePageDisplayHook {
    public function onBeforePageDisplayHook( $out, $skin ) { ... }
}

Converting extensions to the new hook system Conversion to the new system is done by doing the following for each hook handler method:

• identify the hook handler interface, and make the hook handler class implement this interface
• change the name and signature of the hook handler method to be exactly the same as in the interface
• change the hook registration in the "Hooks" section of extension.json to refer to the handler you specified in the "HookHandlers" section.

The process was demonstrated at the Wikimedia Hackathon 2021:

• Recording on YouTube
• Patch on Gerrit

Hook behavior before MediaWiki 1.22 vs after

Extracted from: change 500542: for non-abortable hooks (most hooks) returning true has been redundant since MediaWiki 1.22 (in 2015). This was done to reduce chances of accidental failure because we had experienced several outages and broken features due to silent failures where e.g. one hook callback somewhere accidentally returned a non-bool or false instead of true/void and thus short-circuits the whole system.

(Returning non-true/non-void in a MediaWiki Hook is equivalent to e.preventDefault and e.stopImmediatePropagation in JavaScript events, it kills other listeners for the same event).

For example, if onBeforePageDisplay hook were to return false in MobileFrontend, it would mean Popups stops because its callback would no longer run. See differences below, assuming the hook onBeforePageDisplay.

Before MediaWiki 1.22

public static function onBeforePageDisplay( OutputPage $out, Skin $skin ) {
    // some code
    return true; // explicit
}

or

public static function onBeforePageDisplay( OutputPage $out, Skin $skin ) {
    // some code
    return; // explicit
}

MediaWiki 1.22+

public static function onBeforePageDisplay( OutputPage $out, Skin $skin ) {
    // some code
    // no need for a return true or return
}

Documentation

Currently, hooks in MediaWiki core have to be documented both in hook interface (in the source code repository) and here on MediaWiki.org. In some cases, one of these steps may not yet have been completed, so if a hook appears undocumented, check both.

Each hook provided by MediaWiki Core is defined in a hook interface. Typically, hook interfaces are located in a "Hook" sub-namespace inside the caller namespace. For example, Storage/Hook/PageContentSaveCompleteHook.php. You can find a list of hook interfaces in the generated MediaWiki PHP documentation.

To document a hook on-wiki, use {{MediaWikiHook}}.

As of June 2020, docs/hooks.txt is deprecated as a source of documentation for individual hooks. For more information about the introduction of hooks based on HookContainer, see the hook specification in MediaWiki Core.

Hook interface doc template

In hook interfaces, doc comments specify the status, purpose, parameters, and behavior of the hook.

/**
 * @stable for implementation
 * @ingroup Hooks
 */
interface NameHook {
	/**
	 * This hook is called after/before/when...
	 * Use this hook to...
	 *
	 * @since x.xx
	 *
	 * @param type $name Description
	 * @return bool|void True or no return value to continue or false to abort
	 */
	public function onName( $param );
}

Available hooks

Hooks grouped by function

Some of these hooks can be grouped into multiple functions.

Sections: Article Management - Edit Page - Page Rendering - User Interface - File Management - Special Pages - User Management - Logging - Skinning Templates - API - Import/Export - Diffs - Miscellaneous

Warning:

New hooks are added to MediaWiki fairly frequently, so this list is not always completely up to date. As with most documentation on this site, if you need complete up-to-the-minute information you are advised to consult the generated list of hook interfaces. As ever, you are encouraged to update this list to correct any errors or omissions.

Function	Version	Hook	Description
Article Management	1.23.0	Article::MissingArticleConditions	called when showing a page.
	1.21	ArticleAfterFetchContentObject	(deprecated in 1.32) After fetching content of an article from the database.
	1.16	ArticleConfirmDelete	Occurs before writing the confirmation form for article deletion.
	1.21	ArticleContentViewCustom	(removed in 1.35) allows to output the text of the article in a different format than wikitext
	1.25	ArticleDeleteAfterSuccess	Output after an article has been deleted
	1.4.0	ArticleDeleteComplete	Occurs after the delete article request has been processed
	1.4.0	ArticleDelete	Occurs whenever the software receives a request to delete an article
	1.5.7	ArticleEditUpdateNewTalk	Allows an extension to prevent user notification when a new message is added to their talk page.
	1.6.0	ArticleEditUpdatesDeleteFromRecentchanges	Occurs before saving to the database. If returning false old entries are not deleted from the recentchangeslist.
	1.14.0	ArticleEditUpdates	(deprecated in 1.35) Called when edit updates (mainly link tracking) are made when an article has been changed.
	1.8.0	ArticleFromTitle	Called to determine the class to handle the article rendering, based on title
	1.6.0	ArticleInsertComplete	(removed in 1.29) Occurs after a new article has been created
	1.12.0	ArticleMergeComplete	after merging to article using Special:Mergehistory
	1.36	ArticleParserOptions	This hook is called before parsing wikitext for an article,
	1.18	ArticlePrepareTextForEdit	Called when preparing text to be saved.
	1.4.0	ArticleProtectComplete	Occurs after the protect article request has been processed
	1.4.0	ArticleProtect	Occurs whenever the software receives a request to protect an article
	1.6.0	ArticlePurge	Allows an extension to cancel a purge.
	1.12.0	ArticleRevisionUndeleted	(deprecated in 1.35) Occurs after an article revision is restored
	1.32	ArticleRevisionViewCustom	allows to output the text of an article revision in a different format than wikitext
	1.13.0	ArticleRevisionVisibilitySet	called when changing visibility of one or more revisions of an article
	1.12.0	ArticleRollbackComplete	(deprecated in 1.35) Occurs after an article rollback is completed
	1.4.0	ArticleSaveComplete	(removed in 1.29) (use PageContentSaveComplete) Occurs after the save article request has been processed
	1.4.0	ArticleSave	(removed in 1.29) (use MultiContentSave) Occurs whenever the software receives a request to save an article
	1.21	ArticleUndeleteLogEntry	Occurs when a log entry is generated but not yet saved
	1.9.1	ArticleUndelete	When one or more revisions of an article are restored
	1.11.0	ArticleUpdateBeforeRedirect	Occurs after a page is updated (usually on save), before the user is redirected back to the page
	1.19	ArticleViewCustom	(removed in 1.29) allows to output the text of the article in a different format than wikitext
	1.18	ArticleViewFooter	After showing the footer section of an ordinary page view.
	1.17	CanonicalNamespaces	For extensions adding their own namespaces or altering the defaults.
	1.25	ChangeTagAfterDelete	Called after a change tag has been deleted (that is, removed from all revisions and log entries to which it was applied).
	1.25	ChangeTagCanCreate	Tell whether a change tag should be able to be created by users.
	1.25	ChangeTagCanDelete	Tell whether a change tag should be able to be deleted by users.
	1.28	ChangeTagsAfterUpdateTags	Can be used by extensions to take actions after change tags have been added or updated.
	1.30	ChangeTagsAllowedAdd	Called when checking if a user can add tags to a change.
	1.25	ChangeTagsListActive	Can be used by extensions to register active change tags.
	1.21.0	ContentHandlerDefaultModelFor	called when deciding the default content model for a given title.
	1.21.0	ContentHandlerForModelID	called when a ContentHandler is requested for a given content model name, but no entry for that model exists in $wgContentHandlers .
	1.23	ContentModelCanBeUsedOn	args = $modelId, Title $title, &$ok
	1.21.0	ConvertContent	Called when a conversion to another content model is requested.
	1.29	GetContentModels	Allows to add custom content handlers to the list of content models registered with the system.
	1.19	LanguageGetNamespaces	Provide custom ordering for namespaces or remove namespaces.
	1.25.0	MovePageIsValidMove	Specify whether a page can be moved for technical reasons.
	1.35.0	MultiContentSave	Occurs whenever the software receives a request to save an article
	1.25	MovePageCheckPermissions	Specify whether the user is allowed to move the page.
	1.20	NamespaceIsMovable	Called when determining if it is possible to move pages, for a particular namespace. This controls moves both to and from the given namespace.
	1.13	NewRevisionFromEditComplete	(deprecated in 1.35) Called when a revision was inserted due to an edit.
	1.21	PageContentInsertComplete	(deprecated in 1.35) Occurs after a new article is created
	1.18	PageContentLanguage	Allows changing the page content language and consequently all features depending on that (writing direction, LanguageConverter, ...).
	1.21.0	PageContentSaveComplete	(deprecated in 1.35) Occurs after the save article request has been processed
	1.21.0	PageContentSave	(deprecated in 1.35) (use MultiContentSave) Occurs whenever the software receives a request to save an article
	1.32	PageDeletionDataUpdates	Called when constructing a list of DeferrableUpdate to be executed when a page is deleted.
	1.35	PageMoveComplete	After an article has been moved, post commit
	1.35	PageMoveCompleting	After an article has been moved, pre commit
	1.35	PageSaveComplete	After an article has been updated.
	1.25	PageViewUpdates	Called after a page view is seen by MediaWiki. Note this does not capture views made via external caches such as Squid.
	1.16	ProtectionForm::buildForm	(deprecated in 1.36) Called after all protection type fieldsets are made in the form.
	1.16	ProtectionForm::save	Called when a protection form is submitted.
	1.16	ProtectionForm::showLogExtract	Called after the protection log extract is shown.
	1.36	ProtectionFormAddFormFields	This hook is called after all protection type form fields are added.
	1.8.0	RecentChange_save	Called after a "Recent Change" is committed to the DB
	1.32	RevisionDataUpdates	Called when constructing a list of DeferrableUpdate to be executed to record secondary data about a revision.
	1.35	RevisionFromEditComplete	Called when a revision was inserted due to an edit, file upload, import or page move.
	1.11.0	RevisionInsertComplete	(deprecated in 1.31) (use RevisionRecordInserted) Called after a revision is inserted into the DB
1.31	RevisionRecordInserted	Called after a revision is inserted into the database.
1.35	RevisionUndeleted	Called after an article revision is restored
1.35	RollbackComplete	(deprecated in 1.36) Occurs after an article rollback is completed
1.15	ListDefinedTags	Can be used by extensions to register change tags.
1.6.0	SpecialMovepageAfterMove	Called after a page is moved.
1.14	TitleArrayFromResult	Called when creating an TitleArray object from a database result.
1.24	TitleExists	Called when determining whether a page exists at a given title.
1.22	TitleGetEditNotices	Called when the edit notices for a page are being retrieved.
1.16	TitleGetRestrictionTypes	Allows to modify the types of protection that can be applied.
1.20.0	TitleIsAlwaysKnown	Allows overriding default behaviour for determining if a page exists.
1.19	TitleIsCssOrJsPage	(removed in 1.29) Called when determining if a page is a CSS or JS page.
1.19	TitleIsMovable	Called when determining if it is possible to move a page.
1.19	TitleIsWikitextPage	(removed in 1.29) called when determining if a page is a wikitext or should be handled by seperate handler (via ArticleViewCustom
1.4.0	TitleMoveComplete	(deprecated in 1.35) Occurs whenever a request to move an article is completed
1.27	TitleMoveCompleting	(deprecated in 1.35) Occurs whenever a request to move an article is completed, before the database transaction commits.
1.27	TitleMoveStarting	Before moving an article (title), but just after the atomic DB section starts.
1.22.0	TitleMove	Occurs before a requested pagemove is performed
1.22	TitleQuickPermissions	Called from Title::checkQuickPermissions to allow skipping checking quick Title permissions (e.g., the 'delete' permission).
1.19	TitleReadWhitelist	Called at the end of read permissions checks, just before adding the default error message if nothing allows the user to read the page.
1.18	UndeleteForm::undelete	Called un UndeleteForm::undelete, after checking that the site is not in read-only mode, that the Title object is not null and after a PageArchive object has been constructed but before performing any further processing.
1.21	WikiPageDeletionUpdates	(deprecated in 1.32) manipulate the list of DeferrableUpdates to be applied when a page is deleted. Called in WikiPage::getDeletionUpdates(). Note that updates specific to a content model should be provided by the respective Content's getDeletionUpdates() method.
1.28	WikiPageFactory	Override WikiPage class used for a title
Edit Page	1.21.0	AlternateEditPreview	Allows replacement of the edit preview
	1.6.0	AlternateEdit	Used to replace the entire edit page, altogether.
	1.9.1	CustomEditor	When invoking the page editor. Return true to allow the normal editor to be used, or false if implementing a custom editor, e.g. for a special namespace, etc.
	1.21.0	EditFilterMergedContent	Post-section-merge edit filter
	1.12.0	EditFilterMerged	(removed in 1.29) (use EditFilterMergedContent) Post-section-merge edit filter
	1.6.0	EditFilter	Perform checks on an edit
	1.16	EditFormInitialText	Allows modifying the edit form when editing existing pages
	1.7.0	EditFormPreloadText	Called when edit page for a new article is shown. This lets you fill the text-box of a new page with initial wikitext.
	1.25	EditPage::attemptSave:after	Called after an article save attempt
	1.8.3	EditPage::attemptSave	Called before an article is saved, that is before insertNewArticle() is called
	1.16	EditPage::importFormData	Called when reading the data from the editform, after post
	1.6.0	EditPage::showEditForm:fields	Allows injection of form field into edit form.
	1.6.0	EditPage::showEditForm:initial	Allows injection of HTML into edit form
	1.24	EditPage::showReadOnlyForm:initial	Called just before the read only edit form is rendered
	1.21.0	EditPage::showStandardInputs:options	Allows injection of form fields into the editOptions area
	1.13.0	EditPageBeforeConflictDiff	Allows modifying the EditPage object and output when there's an edit conflict.
	1.12.0	EditPageBeforeEditButtons	Used to modify the edit buttons on the edit form
	1.14.0	EditPageBeforeEditChecks	(removed in 1.32) Allows modifying the edit checks below the textarea in the edit form
	1.16	EditPageBeforeEditToolbar	Allows modifying the edit toolbar above the textarea
	1.16	EditPageCopyrightWarning	Allow for site and per-namespace customization of contribution/copyright notice.
	1.29	EditPageGetCheckboxesDefinition	Allows modifying the edit checkboxes in the edit form
	1.21	EditPageGetDiffContent	Allow modifying the wikitext that will be used in "Show changes". Note that it is preferable to implement diff handling for different data types using the ContentHandler facility.
	1.16	EditPageGetDiffText	(removed in 1.29) Allow modifying the wikitext that will be used in "Show changes"
	1.21	EditPageGetPreviewContent	Allow modifying the wikitext that will be previewed. Note that it is preferable to implement previews for different data types using the ContentHandler facility.
	1.16	EditPageGetPreviewText	(removed in 1.29) Allow modifying the wikitext that will be previewed
	1.16	EditPageNoSuchSection	When a section edit request is given for an non-existent section.
	1.16	EditPageTosSummary	Give a chance for site and per-namespace customizations of terms of service summary link that might exist separately from the copyright notice.
	1.20	FormatAutocomments	When an autocomment is formatted by the Linker.
	1.19	PlaceNewSection	Override placement of new sections.
	1.35	ParserPreSaveTransformComplete	Called from Parser::preSaveTransform() after processing is complete, giving the extension a chance to further modify the wikitext.
Page Rendering	1.27.0	AfterBuildFeedLinks	Executed after all feed links are created.
	1.24	AfterParserFetchFileAndTitle	Alter the HTML code of an image gallery. Called after an image gallery is formed by Parser, just before adding its HTML to parser output.
	1.6.0	ArticleAfterFetchContent	(removed in 1.29) Used to process raw wiki code after most of the other parser processing is complete.
	1.21	ArticleContentViewCustom	(removed in 1.35) allows to output the text of the article in a different format than wikitext
	1.6.0	ArticlePageDataAfter	Executes after loading the data of an article from the database.
	1.6.0	ArticlePageDataBefore	Executes before data is loaded for the article requested.
	1.36	ArticleParserOptions	This hook is called before parsing wikitext for an article,
	1.32	ArticleRevisionViewCustom	allows to output the text of an article revision in a different format than wikitext
	1.19	ArticleViewCustom	(removed in 1.29) allows to output the text of the article in a different format than wikitext
	1.18	ArticleViewFooter	After showing the footer section of an ordinary page view.
	1.6.0	ArticleViewHeader	Called after an articleheader is shown.
	1.5.1	ArticleViewRedirect	Allows an extension to prevent the display of a "Redirected From" link on a redirect page.
	1.7	BadImage	Used to determine if an image exists on the 'bad image list'. Return false to when setting $bad value.
	1.19	BeforeDisplayNoArticleText	Before displaying noarticletext or noarticletext-nopermission messages.
	1.24	BeforeHttpsRedirect	(deprecated in 1.35) Called prior to forcing HTTP->HTTPS redirect. Use this hook to override how the redirect is output.
	1.19	BeforePageRedirect	Called prior to sending an HTTP redirect
	1.18.0	BeforeParserFetchFileAndTitle	Allows an extension to select a different version of an image to link to.
	1.10.1	BeforeParserFetchTemplateAndtitle	(deprecated in 1.36) Allows an extension to specify a version of a page to get for inclusion in a template.
	1.36	BeforeParserFetchTemplateRevisionRecord	This hook is called before a template is fetched by Parser.
	1.10.1	BeforeParserrenderImageGallery	(deprecated in 1.35) Allows an extension to modify an image gallery before it is rendered.
	1.22	CanIPUseHTTPS	(deprecated in 1.35) Called when checking if an IP address can use HTTPS
	1.4.3	CategoryPageView	Called before viewing a categorypage in CategoryPage::view
	1.25	CategoryViewer::doCategoryQuery	Occurs after querying for pages to be displayed in a Category page
	1.25	CategoryViewer::generateLink	Before generating an output link allow extensions opportunity to generate a more specific or relevant link.
	1.25	ContentAlterParserOutput	Customize parser output for a given content object, called by AbstractContent::getParserOutput.
	1.24.0	ContentGetParserOutput	Customize parser output for a given content object, called by AbstractContent::getParserOutput. May be used to override the normal model-specific rendering of page content.
	1.14	DoEditSectionLink	(removed in 1.32) Override the HTML generated for section edit links.
	1.22.0	GalleryGetModes	Allows extensions to add classes that can render different modes of a gallery.
	1.12	GetLinkColours	modify the CSS class of an array of page links
	1.28	HtmlPageLinkRendererBegin	args = LinkRenderer $linkRenderer, LinkTarget $target, &$text, &$extraAttribs, &$query, &$ret
	1.28	HtmlPageLinkRendererEnd	args = LinkRenderer $linkRenderer, LinkTarget $target, $isKnown, &$text, &$attribs, &$ret
	1.13	ImageBeforeProduceHTML	Called before producing the HTML created by a wiki image insertion
	1.11	ImageOpenShowImageInlineBefore	Fired just before showing the image on an image page.
	1.16	ImagePageAfterImageLinks	Called after the image links section on an image page is built.
	1.13	ImagePageFileHistoryLine	Called when a file history line is constructed.
	1.13	ImagePageFindFile	Called when fetching the file associated with an image page.
	1.16	ImagePageShowTOC	Called when fetching the file associed with an image page.
	1.10.0	InternalParseBeforeLinks	Used to process the expanded wiki code after <nowiki>, HTML-comments, and templates have been treated. Suitable for syntax extensions that want to customize the treatment of internal link syntax, i.e. [[....]].
	1.20	InternalParseBeforeSanitize	(deprecated in 1.35) This hook is called during Parser's internalParse method just before the parser removes unwanted/dangerous HTML tags and after nowiki/noinclude/includeonly/onlyinclude and other processings.
	1.13.0	LinkerMakeExternalImage	Called before external image HTML is returned. Used for modifying external image HTML.
	1.13.0	LinkerMakeExternalLink	Called before the HTML for external links is returned. Used for modifying external link HTML.
	1.23.0	LinkerMakeMediaLinkFile	Called before the HTML for media links is returned. Used for modifying media link HTML.
	1.6.0	OutputPageBeforeHTML	Called every time wikitext is added to the OutputPage, after it is parsed but before it is added. Called after the page has been rendered, but before the HTML is displayed.
	1.8.0	OutputPageParserOutput	Called after parse, before the HTML is added to the output.
	1.6.0	PageRenderingHash	Alter the parser cache option hash key.
	1.20	ParserAfterParse	Called from Parser::parse() just after the call to Parser::internalParse() returns.
	1.5.0	ParserAfterStrip	(removed in 1.36) Before version 1.14.0, used to process raw wiki code after text surrounded by ‎<nowiki> tags have been protected but before any other wiki text has been processed. In version 1.14.0 and later, runs immediately after ParserBeforeStrip.
	1.5.0	ParserAfterTidy	Used to add some final processing to the fully-rendered page output.
	1.26	ParserAfterUnstrip	Called after the first unstripGeneral() in Parser::internalParseHalfParsed()
	1.6.0	ParserBeforeInternalParse	Replaces the normal processing of stripped wiki text with custom processing. Used primarily to support alternatives (rather than additions) to the core MediaWiki markup syntax.
	1.35	ParserBeforePreprocess	Called at the beginning of Parser::preprocess()
	1.5.0	ParserBeforeStrip	(removed in 1.36) Used to process the raw wiki code before any internal processing is applied.
	1.5.0	ParserBeforeTidy	(removed in 1.36) Used to process the nearly-rendered html code for the page (but before any html tidying occurs).
	1.26	ParserCacheSaveComplete	Modify ParserOutput safely after it has been saved to cache.
	1.6.0	ParserClearState	Called at the end of Parser::clearState()
	1.21.0	ParserCloned	Called when the Parser object is cloned.
	1.28	ParserFetchTemplate	(deprecated in 1.35) Called when the parser fetches a template
	1.6.0	ParserGetVariableValueSwitch	Assigns a value to a user defined variable.
	1.6.0	ParserGetVariableValueTs	Use this to change the value of the time for the {{LOCAL...}} magic word.
	1.6.0	ParserGetVariableValueVarCache	(deprecated in 1.35) Use this to change the value of the variable cache or return false to not use it.
	1.22	ParserLimitReportFormat	Called for each row in the parser limit report that needs formatting.
	1.22	ParserLimitReportPrepare	Called at the end of Parser:parse() when the parser will include comments about size of the text parsed.
	1.12	ParserLimitReport	(removed in 1.32) called at the end of Parser::parse() when the parser will add a report about size and complexity of the text parsed as a HTML comment
	1.12	ParserMakeImageParams	Alter the parameters used to generate an image before it is generated
1.30	ParserOptionsRegister	allows registering additional parser options
1.31	ParserOutputPostCacheTransform	Called from ParserOutput::getText() to do post-cache transforms.
1.27	ParserOutputStashForEdit	Called when an edit stash parse finishes, before the output is cached.
1.35	ParserPreSaveTransformComplete	Called from Parser::preSaveTransform() after processing is complete, giving the extension a chance to further modify the wikitext.
1.19	ParserSectionCreate	(deprecated in 1.35) Called each time the parser creates a document section from wikitext.
1.26	RejectParserCacheValue	Return false to reject an otherwise usable cached value from the Parser cache.
1.26	ResourceLoaderForeignApiModules	Called from ResourceLoaderForeignApiModule. Use this to add dependencies to 'mediawiki.ForeignApi' module when you wish to override its behavior. See the module docs for more information.
1.17	ResourceLoaderGetConfigVars	Called right before ResourceLoaderStartUpModule::getConfig returns, to set static (not request-specific) configuration variables. Can not depend on current page, current user or current request; see below.
1.25	ResourceLoaderGetLessVars	(removed in 1.31) Allows to add context-based Less variables.
1.18	ResourceLoaderGetStartupModules	Run once the startup module is being generated.
1.29	ResourceLoaderJqueryMsgModuleMagicWords	Called in ResourceLoaderJqueryMsgModule to allow adding magic words for jQueryMsg. The key is an all-caps magic word, and the value is a string; values depend only on the ResourceLoaderContext
1.17.0	ResourceLoaderRegisterModules	Allows registering modules with ResourceLoader
1.35	ResourceLoaderSiteModulePages	Allows to change which wiki pages comprise the `site` module in given skin.
1.35	ResourceLoaderSiteStylesModulePages	Allows to change which wiki pages comprise the 'site.styles' module in given skin.
1.19	ResourceLoaderTestModules	(deprecated in 1.33) Add new javascript test suites. This is called after the addition of MediaWiki core test suites.
1.24.0	SidebarBeforeOutput	Directly before the sidebar is output
1.16	ShowMissingArticle	Called when generating the output for a non-existent page.
1.11	ShowRawCssJs	(removed in 1.29) Customize the output of raw CSS and JavaScript in page views
User Interface	1.18	ActionBeforeFormDisplay	Before executing the HTMLForm object
	1.18	ActionModifyFormFields	Before creating an HTMLForm object for a page action; allows to change the fields on the form that will be generated.
	1.20	AfterFinalPageOutput	Nearly at the end of OutputPage::output().
	1.9.1	AjaxAddScript	Called in output page just before the initialization
	1.5.7	ArticleEditUpdateNewTalk	Before updating user_newtalk when a user talk page was changed.
	1.6.0	ArticlePurge	Executes before running "&action=purge"
	1.32	ArticleShowPatrolFooter	can be used to hide the [mark as patrolled] link in certain circumstances
	1.18.0	BeforeWelcomeCreation	Allows an extension to change the message displayed upon a successful login.
	1.32	ContentSecurityPolicyDefaultSource	Modify the allowed CSP load sources. This affects all directives except for the script directive.
	1.32	ContentSecurityPolicyDirectives	Modify the content security policy directives.
	1.32	ContentSecurityPolicyScriptSource	Modify the allowed CSP script sources.
	1.4.0	EmailUserComplete	Occurs after an email has been sent from one user to another
	1.4.0	EmailUser	Occurs whenever the software receives a request to send an email from one user to another
	1.21	GetHumanTimestamp	Pre-emptively override the human-readable timestamp generated by MWTimestamp::getHumanTimestamp(). Return false in this hook to use the custom output.
	1.31	GetLangPreferredVariant	allows fetching the language variant code from cookies or other such alternative storage.
	1.22	GetNewMessagesAlert	Disable or modify the new messages alert before it is shown
	1.16	GetPreferences	Modify user preferences.
	1.22	GetRelativeTimestamp	Pre-emptively override the relative timestamp generated by MWTimestamp::getRelativeTimestamp(). Return false in this hook to use the custom output.
	1.32	HistoryPageToolLinks	Allows adding links to the revision history page subtitle.
	1.21	HistoryRevisionTools	(deprecated in 1.35) Override or extend the revision tools available from the page history view, i.e. undo, rollback, etc.
	1.35	HistoryTools	Use this hook to override or extend the revision tools available from the page history view, i.e. undo, rollback, etc.
	1.24	LanguageSelector	Hook to change the language selector available on a page.
	1.6.0	MarkPatrolledComplete	Called after an edit is marked patrolled
	1.6.0	MarkPatrolled	Called before an edit is marked patrolled
	1.14	MakeGlobalVariablesScript	right before OutputPage->getJSVars returns the vars.
	1.32	OutputPageAfterGetHeadLinksArray	Allows extensions to modify the HTML metadata in the ‎<head> element
	1.17	OutputPageBodyAttributes	Called when OutputPage::headElement() is creating the body tag.
	1.14	OutputPageCheckLastModified	When checking if the page has been modified since the last visit
	1.13	OutputPageMakeCategoryLinks	Called when links are about to be generated for the page's categories.
	1.10	PageHistoryBeforeList	When a history page list is about to be constructed.
	1.10	PageHistoryLineEnding	right before the end ‎<li> is added to a history line.
	1.26	PageHistoryPager::doBatchLookups	allow performing batch lookups for prefetching information needed for display
	1.13	PageHistoryPager::getQueryInfo	When a history pager query parameter set is constructed.
	1.10	RawPageViewBeforeOutput	called before displaying a page with action=raw. Returns true if display is allowed, false if display is not allowed.
	1.16	ShowSearchHitTitle	Customize display of search hit title/link.
	1.21	ShowSearchHit	Customize display of search hit.
	1.7	SiteNoticeAfter	Used to modify the site notice after it has been created from $wgSiteNotice or interface messages.
	1.7	SiteNoticeBefore	Used to modify the sitenotice before it has been created from $wgSiteNotice. Return false to suppress or modify default site notice.
	1.6.0	SpecialMovepageAfterMove	Called after a page is moved.
	1.19.0	SpecialSearchCreateLink	Called when making the message to create a page or go to an existing page
	1.6.0	SpecialSearchNogomatch	Called when the 'Go' feature is triggered and the target doesn't exist. Full text search results are generated after this hook is called
	1.19.0	SpecialSearchPowerBox	the equivalent of SpecialSearchProfileForm for the advanced form
	1.34	UndeletePageToolLinks	Add one or more links to edit page subtitle when a page has been previously deleted.
	1.4.0	UnwatchArticleComplete	Occurs after the unwatch article request has been processed
	1.4.0	UnwatchArticle	Occurs whenever the software receives a request to unwatch an article
	1.5.7	UserClearNewTalkNotification	called when clearing the "You have new messages!" message, return false to not delete it
	1.4.0	UserLoginComplete	Occurs after a user has successfully logged in
	1.4.0	UserLogoutComplete	Occurs after a user has successfully logged out
	1.4.0	UserLogout	Occurs when the software receives a request to log out
	1.5.7	UserRetrieveNewTalks	(deprecated in 1.35) called when retrieving "You have new messages!" message(s)
	1.19	UserToolLinksEdit	Contribs | Block)"
	1.4.0	WatchArticleComplete	Occurs after the watch article request has been processed
	1.4.0	WatchArticle	Occurs whenever the software receives a request to watch an article
File Management	1.19	BitmapHandlerCheckImageArea	Called by BitmapHandler::normaliseParams(), after all normalizations have been performed, except for the $wgMaxImageArea check.
	1.18	BitmapHandlerTransform	Before a file is transformed, gives extension the possibility to transform it themselves.
	1.18.1	ExtractThumbParameters	(removed in 1.30) Called when extracting thumbnail parameters from a thumbnail file name.
	1.13	FileDeleteComplete	When a file is deleted
	1.20	FileTransformed	When a file is transformed and moved into storage.
	1.13	FileUndeleteComplete	When a file is undeleted
	1.11	FileUpload	Fires when a local file upload occurs.
	1.18	GetMetadataVersion	Allows to modify the image metadata version currently in use.
	1.23.0	GetExtendedMetadata	Allows including additional file metadata information in the imageinfo API.
	1.24	HTMLFileCache::useFileCache	Override whether a page should be cached in file cache.
	1.10.0	IsFileCacheable	Allow an extension to disable file caching on pages.
	1.22	IsUploadAllowedFromUrl	Allows overriding the result of UploadFromUrl::isAllowedUrl()
	1.16.0	ImgAuthBeforeStream	Executed before file is streamed to user, but only when using img_auth
	1.34	ImgAuthModifyHeaders	Executed just before a file is streamed to a user, allowing headers to be modified beforehand.
	1.13	LocalFile::getHistory	Called before file history query performed.
	1.19	LocalFilePurgeThumbnails	Called before thumbnails for a local file are purged.
	1.21	ThumbnailBeforeProduceHTML	Called before an image HTML is about to be rendered (by ThumbnailImage:toHtml method).
	1.16	UploadCreateFromRequest	When UploadBase::createFromRequest has been called
	1.9.0	UploadForm:BeforeProcessing	Called just before the file data (for example description) are processed, so extensions have a chance to manipulate them.
	1.31	UploadForm:getInitialPageText	After the initial page text for file uploads is generated, to allow it to be altered.
	1.16	UploadFormInitDescriptor	Occurs after the descriptor for the upload form as been assembled.
	1.16	UploadFormSourceDescriptors	Occurs after the standard source inputs have been added to the descriptor.
	1.28	UploadStashFile	Occurs before a file is stashed (uploaded to stash).
	1.6.4	UploadComplete	Called when a file upload has completed.
	1.6.0	UploadVerification	(removed in 1.34) (use UploadVerifyFile) Called when a file is uploaded, to allow extra file verification to take place
	1.17	UploadVerifyFile	Called when a file is uploaded, to allow extra file verification to take place
	1.28	UploadVerifyUpload	(preferred) Can be used to reject a file upload. Unlike 'UploadVerifyFile' it provides information about upload comment and the file description page, but does not run for uploads to stash.
	1.23	ValidateExtendedMetadataCache	Called to validate the cached metadata in FormatMetadata::getExtendedMeta (return false means cache will be invalidated and the GetExtendedMetadata hook will called again).
	1.18	XMPGetInfo	Called when obtaining the list of XMP tags to extract.
	1.18	XMPGetResults	Called just before returning the results array of parsing xmp data.
Special pages	1.32	AncientPagesQuery	Allows modifying the query used by Special:AncientPages.
	1.9.1	BookInformation	Hook to allow extensions to insert additional HTML to a list of book sources e.g. for API-interacting plugins and so on
	1.23	ChangesListInitRows	Batch process change list rows prior to rendering.
	1.12	ChangesListInsertArticleLink	Override or augment link to article in RC list.
	1.23	ChangesListSpecialPageFilters	Called after building form options on pages inheriting from ChangesListSpecialPage (in core: RecentChanges, RecentChangesLinked and Watchlist).
	1.24	ChangesListSpecialPageQuery	Called when building SQL query on pages inheriting from ChangesListSpecialPage (in core: RecentChanges, RecentChangesLinked and Watchlist).
	1.29	ChangesListSpecialPageStructuredFilters	Called to allow extensions to register filters for pages inheriting from ChangesListSpecialPage (in core: RecentChanges, RecentChangesLinked, and Watchlist).
	1.13	ContribsPager::getQueryInfo	Called before the contributions query is about to run
	1.20	ContribsPager::reallyDoQuery	Called before really executing the query for Special:Contributions.
	1.13	ContributionsLineEnding	Called before an HTML line for Special:Contributions is finished
	1.11	ContributionsToolLinks	Change tool links above Special:Contributions
	1.24	DeletedContribsPager::reallyDoQuery	Called before really executing the query for Special:DeletedContributions
	1.24	DeletedContributionsLineEnding	Called before an HTML line for Special:DeletedContributions is finished.
	1.17	EmailUserCC	Occurs before sending the copy of the email to the author
	1.17	EmailUserForm	Occurs after building the email user form object
	1.16	EmailUserPermissionsErrors	Retrieve permissions errors for emailing a user.
	1.25	EnhancedChangesList::getLogText	allows altering, removing or adding to the links of a group of changes in EnhancedChangesList.
	1.26	EnhancedChangesListModifyBlockLineData	Modify data used to build a non-grouped entry in Special:RecentChanges
	1.26	EnhancedChangesListModifyLineData	Modify data used to build a grouped recent change inner line in Special:RecentChanges
	1.7	FetchChangesList	Allows extension to modify a recent changes list for a user
	1.20	GitViewers	Called when generating the list of git viewers for Special:Version, use this to change the list.
	1.9	LanguageGetSpecialPageAliases	(removed in 1.33) Use to define aliases of special pages names depending of the language.
	1.30	NewPagesLineEnding	Called before an HTML line for Special:NewPages is finished.
	1.23	LonelyPagesQuery	Allows modifying the query used by Special:LonelyPages.
	1.14	OldChangesListRecentChangesLine	Customize entire Recent Changes line
	1.23	PreferencesFormPreSave	Allows last minute changes to a user's preferences (via User#setOption) before they're saved and gives a possibility to check which options were modified.
	1.19	PreferencesGetLegend	Override the text used for the ‎<legend> of a preferences section.
	1.26	RandomPageQuery	Modify the query used by Special:Random
	1.20	RedirectSpecialArticleRedirectParams	Lets you alter the set of parameter names such as "oldid" that are preserved when using redirecting special pages such as Special:MyPage and Special:MyTalk.
	1.27	ShortPagesQuery	Allow extensions to modify the query used by Special:ShortPages.
	1.24.0	SpecialBlockModifyFormFields	Add or modify block fields of Special:Block
	1.27	SpecialContributions::getForm::filters	Called with a list of filters to render on Special:Contributions.
	1.28.0	SpecialContributions::formatRow::flags	Called before rendering a Special:Contributions row.
	1.5.0	SpecialContributionsBeforeMainOutput	Before the form on Special:Contributions
	1.13.0	SpecialListusersDefaultQuery	Called right before the end of UsersPager::getDefaultQuery()
	1.13.0	SpecialListusersFormatRow	Called right before the end of UsersPager::formatRow()
	1.13.0	SpecialListusersHeaderForm	Called before adding the submit button in UsersPager::getPageHeader()
	1.13.0	SpecialListusersHeader	Called before closing the ‎<fieldset> in UsersPager::getPageHeader()
	1.13.0	SpecialListusersQueryInfo	Called right before the end of UsersPager::getQueryInfo()
	1.34	SpecialMuteModifyFormFields	Allows modifying HTMLForm fields for Special:Mute
	1.34	SpecialMuteSubmit	(deprecated in 1.34) Used only for instrumentation on SpecialMute
	1.17	SpecialNewpagesConditions	Called when building the SQL query for Special:NewPages.
	1.18	SpecialNewPagesFilters	Called after building form options at NewPages.
	1.7.0	SpecialPage_initList	Called after the Special Page list is populated
	1.20	SpecialPageAfterExecute	Called after SpecialPage::execute().
	1.20	SpecialPageBeforeExecute	Called before SpecialPage::execute().
	1.24	SpecialPageBeforeFormDisplay	Before executing the HTMLForm object
	1.18	SpecialPasswordResetOnSubmit	Called when executing a form submission on Special:PasswordReset.
	1.16	SpecialRandomGetRandomTitle	Modify the selection criteria for Special:Random
	1.18	SpecialRecentChangesFilters	(removed in 1.32) Called after building form options at RecentChanges.
	1.13	SpecialRecentChangesPanel	Called when building form options in SpecialRecentChanges.
	1.13	SpecialRecentChangesQuery	(removed in 1.32) Called when building sql query for SpecialRecentChanges.
	1.22	SpecialResetTokensTokens	Called when building token list for SpecialResetTokens.
	1.27	SpecialSearchGoResult	Called before the 'go' feature of SpecialSearch redirects a user. May provide it's own url to redirect to.
	1.18	SpecialSearchProfileForm	allows modification of search profile forms
	1.16	SpecialSearchProfiles	Allows modification of search profiles.
	1.21	SpecialSearchResultsAppend	Called after all search results HTML has been output. Note that in some cases, this hook will not be called (no results, too many results, SpecialSearchResultsPrepend returned false, etc).
	1.21	SpecialSearchResultsPrepend	'SpecialSearchResultsPrepend': Called immediately before returning HTML on the search results page. Useful for including an external search provider. To disable the output of MediaWiki search output, return false.
	1.13	SpecialSearchResults	called before search result display when there are matches
	1.18	SpecialSearchSetupEngine	allows passing custom data to search engine
	1.16	SpecialStatsAddExtra	Can be used to add extra statistic at the end of Special:Statistics.
	1.29	SpecialTrackingCategories::generateCatLink	Called for each category link on Special:TrackingCategories
	1.29	SpecialTrackingCategories::preprocess	Called after LinkBatch on Special:TrackingCategories
	1.16	SpecialUploadComplete	Called after successfully uploading a file from Special:Upload
1.21	SpecialVersionVersionUrl	Called when building the URL for Special:Version.
1.18	SpecialWatchlistFilters	(removed in 1.32) Called after building form options for Special:Watchlist.
1.22	SpecialWatchlistGetNonRevisionTypes	Allows extensions to register the value they have inserted to rc_type field of recentchanges for non-revision changes so they can be included in the watchlist.
1.14	SpecialWatchlistQuery	(removed in 1.32) Called when building sql query for Special:Watchlist
1.26	SpecialWhatLinksHereLinks	Called every time a list of links is built for a list item for Special:WhatLinksHere
1.18	UndeleteForm::showHistory	Called in UndeleteForm::showHistory, after a PageArchive object has been created but before any further processing is done.
1.18	UndeleteForm::showRevision	Called in UndeleteForm::showRevision, after a PageArchive object has been created but before any further processing is done.
1.18	UndeleteForm::undelete	Called un UndeleteForm::undelete, after checking that the site is not in read-only mode, that the Title object is not null and after a PageArchive object has been constructed but before performing any further processing.
1.9	UndeleteShowRevision	(deprecated in 1.35) called when showing a revision in Special:Undelete
1.9.0	UploadForm:initial	Called just before the upload form is generated
1.28	UsersPagerDoBatchLookups	Give extensions providing user group data from an alternate source a chance to add their data into the cache array so that things like global user groups are displayed correctly in Special:ListUsers.
1.18	WantedPages::getQueryInfo	Called in WantedPagesPage::getQueryInfo(), can be used to alter the SQL query which gets the list of wanted pages.
1.24	WatchlistEditorBeforeFormRender	Occurs before building the Special:EditWatchlist form, used to manipulate the list of pages or preload data based on that list.
1.17	WatchlistEditorBuildRemoveLine	Occurs when building remove lines in Special:Watchlist/edit
1.24.0	WhatLinksHereProps	Allows extensions to annotate WhatLinksHere entries.
User Management	1.18	AbortAutoAccount	(removed in 1.33) Allow to cancel automated local account creation, where normally authentication against an external auth plugin would be creating a local account.
	1.13	AbortAutoblock	Allow extension to cancel an autoblock.
	1.19.5	AbortChangePassword	(removed in 1.27) Return false to cancel password change.
	1.20	AbortEmailNotification	Can be used to cancel email notifications for an edit.
	1.11	AbortLogin	(removed in 1.33) Can cancel the login process
	1.5.8	AbortNewAccount	(removed in 1.33) Can be used to cancel user account creation
	1.22	AbortTalkPageEmailNotification	Disable email notifications of edits to users' talk pages.
	1.5.0	AddNewAccount	(deprecated in 1.27) Called after a user account is created
	1.27	AuthManagerLoginAuthenticateAudit	A login attempt either succeeded or failed for a reason other than misconfiguration or session loss. No return data is accepted; this hook is for auditing only.
	1.13	AuthPluginAutoCreate	(deprecated in 1.27) Called when creating a local account for an user logged in from an external authentication method
	1.9.1	AuthPluginSetup	(deprecated in 1.27) Update or replace authentication plugin object ($wgAuth).
	1.12	AutopromoteCondition	check autopromote condition for user.
	1.32	BeforeResetNotificationTimestamp	Allows prevention of clearing of notification timestamp when a user views a page in their watchlist.
	1.4.0	BlockIpComplete	Occurs after the request to block (or change block settings of) an IP or user has been processed
	1.4.0	BlockIp	Occurs whenever the software receives a request to block (or change the block settings of) an IP address or user
	1.27	ChangeAuthenticationDataAudit	called when user changes authentication data
	1.20	ChangePasswordForm	(removed in 1.34) For extensions that need to add a field to the ChangePassword form via the Preferences form.
	1.29.0	ChangeUserGroups	Called before a user's group memberships are changed
	1.16	ConfirmEmailComplete	Called after a user's email has been confirmed successfully
	1.31	DeleteUnknownPreferences	Called by the cleanupPreferences.php maintenance script to build a WHERE clause with which to delete preferences that are not known about.
	1.7	EmailConfirmed	Replace default way to check whether user's email is confirmed
	1.19	ExemptFromAccountCreationThrottle	To add an exemption from the account creation throttle
	1.37	GetAllBlockActions	Add an action that can be blocked via a partial block.
	1.6.0	GetBlockedStatus	(removed in 1.35) Fired after the user's getBlockStatus is set
	1.34	GetUserBlock	Modify the block found by the block manager.
	1.12	getUserPermissionsErrors	Add a permissions error when permissions errors are checked for.
	1.12	getUserPermissionsErrorsExpensive	Same as getUserPermissionsErrors as but called only if expensive checks are enabled
	1.13	GetAutoPromoteGroups	When determining which autopromote groups a user is entitled to be in.
	1.16	InvalidateEmailComplete	Called after a user's email has been invalidated successfully.
	1.9	IsTrustedProxy	Allows an extension to set an IP as trusted or not.
	1.12	isValidEmailAddr	Override the result of Sanitizer::validateEmail().
	1.11	isValidPassword	Override the result of User::isValidPassword()
	1.26.0	LocalUserCreated	Called immediately after a local user has been created and saved to the database.
	1.10	LoginAuthenticateAudit	(removed in 1.27) A login attempt for a valid user account either succeeded or failed. No return data is accepted; this hook is for auditing only.
	1.23	LoginPasswordResetMessage	(removed in 1.27) called when the user is being requested to reset their password on login.
	1.26	LoginUserMigrated	(removed in 1.33) allows extensions to inform a user that their username doesn't exist for a specific reason
	1.26	PasswordPoliciesForUser	Alter the effective password policy for a user.
	1.18	PerformRetroactiveAutoblock	Called before a retroactive autoblock is applied to a user.
	1.9	PingLimiter	Allows extensions to override the results of User::pingLimiter()
	1.11	PrefsEmailAudit	called when user changes his email address
	1.11	PrefsPasswordAudit	(removed in 1.27) called when user changes his password
	1.23	ResetPasswordExpiration	Allow extensions to set a default password expiration
	1.37	SaveUserOptions	Called just before saving user preferences. This hook replaces UserSaveOptions . Hook handlers can either add or manipulate options, or reset one back to its default to block changing it. Hook handlers are also allowed to abort the process by returning false, e.g. to save to a global profile instead. Compare to the UserSaveSettings hook, which is called after the preferences have been saved.
	1.27.0	SecuritySensitiveOperationStatus	Affect the return value from AuthManager::securitySensitiveOperationStatus()
	1.27.0	SessionCheckInfo	Validate session info as it's being loaded from storage
	1.27.0	SessionMetadata	Add metadata to a session being saved
	1.21	UpdateUserMailerFormattedPageStatus	Occurs before a notification email gets sent.
	1.29.0	UnblockUserComplete	Occurs after the request to unblock an IP or user has been processed
	1.29.0	UnblockUser	Occurs whenever the software receives a request to unblock an IP address or user
	1.14	User::mailPasswordInternal	Before creation and mailing of a user's new temporary password.
	1.18	UserAddGroup	Called when adding a group to an user.
	1.13	UserArrayFromResult	called when creating an UserArray object from a database result.
	1.6.0	userCan	To interrupt/advise the "user can do X to Y article" check
	1.12	UserCanSendEmail	Allows overriding the permission check in User::canSendEmail()
	1.6	UserCreateForm	(removed in 1.33) Manipulate the user create form
	1.11	UserEffectiveGroups	Dynamically add or remove to the default user groups provided by the database table User groups table
	1.13	UserGetAllRights	After calculating a list of all available rights
	1.18	UserGetDefaultOptions	Called after fetching the core default user options.
	1.13	UserGetEmailAuthenticationTimestamp	Called when getting the timestamp of email authentification.
	1.13	UserGetEmail	Called when getting an user email address.
	1.11	UserGetImplicitGroups	(removed in 1.32) Dynamically adds to or removes from the list of available groups.
	1.18	UserGetLanguageObject	Called when getting user's interface language object.
	1.14	UserGetReservedNames	Allows to modify $wgReservedUsernames at run time.
	1.32.0	UserGetRightsRemove	Called in User::getRights() to dynamically remove rights
1.11.0	UserGetRights	Called in User::getRights() to dynamically add rights
1.26	UserGroupsChanged	Called after user groups are changed.
1.16	UserIsBlockedFrom	Check if a user is blocked from a specific page (for specific block exemptions).
1.14	UserIsBlockedGlobally	Runs before User::mBlockedGlobally is set; can be used to change the blocked status of an IP address or a user
1.28	UserIsBot	Occurs when determining whether a user is a bot account
1.26.0	UserIsLocked	Fired to check if a user account is locked
1.22	UserIsEveryoneAllowed	Check if all users are allowed some user right; return false if a UserGetRights hook might remove the named right.
1.26	UserIsHidden	(removed in 1.35) Check if the user's name should be hidden. See User::isHidden().
1.14	UserLoadAfterLoadFromSession	Called to authenticate users on external/environmental means; occurs after session is loaded
1.13	UserLoadDefaults	Called when loading a default user
1.15	UserLoadFromDatabase	Called when loading a user from the database.
1.13	UserLoadFromSession	(removed in 1.34) Called to authenticate users on external/environmental means.
1.16	UserLoadOptions	When user options/preferences are being loaded from the database.
1.27.0	UserLoggedIn	Called after a user is logged in
1.6	UserLoginForm	(deprecated in 1.27) Change to manipulate the login form
1.27	UserMailerSplitTo	Called in UserMailer::send() to give extensions a chance to split up an email with multiple of the To: field into separate emails.
1.27	UserMailerTransformContent	Allow transformation of content, such as encrypting/signing
1.27	UserMailerTransformMessage	Called in UserMailer::send() to change email after it has gone through the MIME transform. Extensions can block sending the email by returning false and setting $error.
1.18	UserRemoveGroup	Called when removing a group from an user.
1.6.0	UserRights	(removed in 1.34) (use UserGroupsChanged) Called after a user's group memberships are changed
1.22	UserRequiresHTTPS	(deprecated in 1.35) Allows extensions to override whether users need to be redirected to HTTPS
1.24	UserResetAllOptions	Allows changing the behavior when a user's preferences are reset. For instance, certain preferences can be preserved.
1.16	UserSaveOptions	Called just before saving user preferences. Hook handlers can either add or manipulate options, or reset one back to its default to block changing it. Hook handlers are also allowed to abort the process by returning false, e.g. to save to a global profile instead. Compare to the UserSaveSettings hook, which is called after the preferences have been saved.
1.13	UserSaveSettings	Called directly after user preferences (user_properties in the database) have been saved. Compare to the UserSaveOptions hook, which is called before.
1.33	UserSendConfirmationMail	Called just before a confirmation email is sent to a user. Hook handlers can modify the email that will be sent.
1.13	UserSetCookies	(deprecated in 1.27) Called when setting user cookies
1.13	UserSetEmailAuthenticationTimestamp	Called when setting the timestamp of email authentication.
1.13	UserSetEmail	Called when changing user email address.
Logging	1.23	GetLogTypesOnUser	Add log types where the target is a userpage
	1.26.0	LogException	Called before an exception (or PHP error) is logged.
	1.25	LogEventsListGetExtraInputs	When getting extra inputs to display on Special:Log for a specific log type
	1.30	LogEventsListLineEnding	Called before an HTML line for Special:Log is finished
	1.19	LogEventsListShowLogExtract	Called before the result of LogEventsList::showLogExtract() is added to OutputPage.
	1.12	LogLine	Processes a single log entry on Special:Log
	1.33	ManualLogEntryBeforePublish	Lets extensions tag log entries when actions are performed
	1.29	OtherAutoblockLogLink	Get links to the autoblock log from extensions which autoblocks users and/or IP addresses too..
	1.16	OtherBlockLogLink	Get links to the block log from extensions which blocks users and/or IP addresses too.
	1.24	SpecialLogAddLogSearchRelations	Add log relations to the current log
Skinning / Templates	1.27.0	AuthChangeFormFields	Allows modification of AuthManager-based forms
	1.23.0	BaseTemplateAfterPortlet	(deprecated in 1.35) (SkinTemplate.php) After rendering of portlets.
	1.18	BaseTemplateToolbox	(deprecated in 1.35) Called by BaseTemplate when building the toolbox array and returning it for the skin to output.
	1.7.0	BeforePageDisplay	Allows last minute changes to the output page, e.g. adding of CSS or JavaScript by extensions.
	1.25.0	LoginFormValidErrorMessages	Allows to add additional error messages (SpecialUserLogin.php).
	1.25.0	MinervaDiscoveryTools	Allow other extensions to add or override discovery tools (SkinMinerva.php).
	1.6.0	MonoBookTemplateToolboxEnd	Called by Monobook skin after toolbox links have been rendered (useful for adding more)
	1.7.0	PersonalUrls	(SkinTemplate.php) Called after the list of personal URLs (links at the top in Monobook) has been populated.
	1.24.0	PostLoginRedirect	(SpecialUserlogin.php) Modify the post login redirect behavior.
	1.19	RequestContextCreateSkin	Called when creating a skin instance.
	1.35	SkinAddFooterLinks	Add items to the footer for skins using SkinAddFooterLinks
	1.11.0	SkinAfterBottomScripts	(Skin.php) At the end of Skin::bottomScripts()
	1.14	SkinAfterContent	Allows extensions to add text after the page content and article metadata.
	1.35	SkinAfterPortlet	Occurs whenever a page is rendered and allows to add HTML after portlets have been put out.
	1.14	SkinBuildSidebar	At the end of Skin::buildSidebar().
	1.16	SkinCopyrightFooter	Allow for site and per-namespace customization of copyright notice.
	1.25	SkinEditSectionLinks	Modify the section edit links. Called when section headers are created.
	1.17	SkinGetPoweredBy	Called when generating the code used to display the "Powered by MediaWiki" icon.
	1.36	SkinPageReadyConfig	Allows skins to change the `mediawiki.page.ready` module configuration.
	1.24	SkinPreloadExistence	modify the CSS class of an array of page links
	1.12.0	SkinSubPageSubtitle	(Skin.php) Called before the list of subpage links on top of a subpage is generated
	1.6.0	SkinTemplateBuildNavUrlsNav_urlsAfterPermalink	(deprecated in 1.35) Called after the permalink has been entered in navigation URL array.
	1.23.0	SkinTemplateGetLanguageLink	Called after building the data for a language link from which the actual html is constructed.
	1.18.0	SkinTemplateNavigation::SpecialPage	Called on special pages after the special tab is added but before variants have been added
	1.18.0	SkinTemplateNavigation::Universal	Called on both content and special pages after variants have been added
	1.16.0	SkinTemplateNavigation	Called on content pages only after tabs have been added, but before variants have been added. See the other two SkinTemplateNavigation hooks for other points tabs can be modified at.
	1.10	SkinTemplateOutputPageBeforeExec	(deprecated in 1.35) allows further setup of the template engine after all standard setup has been performed but before the skin has been rendered
	1.6.0	SkinTemplatePreventOtherActiveTabs	(deprecated in 1.35) Called to enable/disable the inclusion of additional tabs to the skin.
	1.12	SkinTemplateTabAction	(deprecated in 1.35) Override SkinTemplate::tabAction().
	1.13	SkinTemplateToolboxEnd	(deprecated in 1.35) Called by SkinTemplate skins after toolbox links have been rendered (useful for adding more)
API	1.14.0	APIAfterExecute	Use this hook to extend core API modules
	1.23.0	ApiBeforeMain	Called before ApiMain is executed
	1.20	ApiCheckCanExecute	Called during ApiMain::checkCanExecute().
	1.29	ApiDeprecationHelp	Add messages to the 'deprecation-help' warning generated from ApiBase::addDeprecation().
	1.13.0	APIEditBeforeSave	(removed in 1.34) Called right before saving an edit submitted through api.php?action=edit
	1.25	ApiFormatHighlight	Use to syntax-highlight API pretty-printed output. When highlighting, add output to $context->getOutput() and return false.
	1.14.0	APIGetAllowedParams	Use this hook to modify a module's parameters
	1.25	APIGetDescriptionMessages	Allows to modify a module's help message
	1.19	APIGetDescription	(removed in 1.33) Use this hook to modify a module's descriptions
	1.25	APIGetParamDescriptionMessages	Allows to modify a module's parameter descriptions
	1.14.0	APIGetParamDescription	(removed in 1.33) Use this hook to modify a module's parameter descriptions
	1.25	APIHelpModifyOutput	Allows to modify an API module's help output
	1.25	ApiMain::moduleManager	can be used to conditionally register API modules
	1.20	ApiMain::onException	Called by ApiMain::executeActionWithErrorHandling() when an exception is thrown during API action execution.
	1.28	ApiMakeParserOptions	allows extensions to adjust the parser options before parsing
	1.32	ApiMaxLagInfo	Called right before giving out information about max lag in API
	1.25.0	ApiOpenSearchSuggest	Called when constructing the OpenSearch results. Hooks can alter or append to the array.
	1.33	ApiOptions	Called by action=options before applying changes to user preferences.
	1.32	ApiParseMakeOutputPage	Called when preparing the OutputPage object for ApiParse. This is mainly intended for calling OutputPage::addContentOverride() or OutputPage::addContentOverrideCallback().
	1.25	ApiQuery::moduleManager	Called when ApiQuery has finished initializing its module manager
	1.14.0	APIQueryAfterExecute	Use this hook to extend core API query modules
	1.28	ApiQueryBaseAfterQuery	Called for (some) API query modules after the database query has returned.
	1.28	ApiQueryBaseBeforeQuery	Called for (some) API query modules before a database query is made.
	1.28	ApiQueryBaseProcessRow	Called for (some) API query modules as each row of the database result is processed.
	1.14.0	APIQueryGeneratorAfterExecute	Use this hook to extend core API query modules
	1.13.0	APIQueryInfoTokens	(removed in 1.36) Use this hook to add custom tokens to prop=info
	1.14.0	APIQueryRecentChangesTokens	(removed in 1.36) Use this hook to add custom tokens to list=recentchanges
	1.13.0	APIQueryRevisionsTokens	(removed in 1.36) Use this hook to add custom tokens to prop=revisions
	1.18	APIQuerySiteInfoGeneralInfo	Used to add extra information to the SiteInfo general information output
	1.22	APIQuerySiteInfoStatisticsInfo	Used to add extra information to the SiteInfo statistics information output
	1.24	ApiQueryTokensRegisterTypes	Use this hook to add additional token types to action=query&meta=tokens. Note that most modules will probably be able to use the 'csrf' token instead of creating their own token types.
	1.15	APIQueryUsersTokens	(removed in 1.36) Use this hook to add custom token to list=users.
	1.29	ApiQueryWatchlistExtractOutputData	extract row data for ApiQueryWatchlist
	1.29	ApiQueryWatchlistPrepareWatchedItemQueryServiceOptions	Populate the options to be passed from ApiQueryWatchlist to WatchedItemQueryService.
	1.17	ApiRsdServiceApis	Add or remove APIs from the RSD services list.
	1.20	ApiTokensGetTokenTypes	(removed in 1.36) Use this hook to extend action=tokens with new token types.
	1.29	ApiValidatePassword	This will allow for checking passwords against the wiki's password
	1.23.0	AddNewAccountApiForm	(deprecated in 1.27) Allows modifying the internal login form when creating an account via the API.
	1.23.0	AddNewAccountApiResult	(deprecated in 1.27) Modifies the API output when an account is created via the API.
Import/Export	1.17.0	AfterImportPage	When a page import is completed
	1.17.0	ImportHandleLogItemXMLTag	When parsing a XML tag in a log item
	1.17.0	ImportHandlePageXMLTag	When parsing a XML tag in a page
	1.17.0	ImportHandleRevisionXMLTag	When parsing a XML tag in a page revision
	1.17.0	ImportHandleToplevelXMLTag	When parsing a top level XML tag
	1.31	ImportHandleUnknownUser	When a user doesn't exist locally, this hook is called to give extensions an opportunity to auto-create it. If the auto-creation is successful, return false.
	1.17.0	ImportHandleUploadXMLTag	When parsing a XML tag in a file upload
	1.27	ImportLogInterwikiLink	Hook to change the interwiki link used in log entries and edit summaries for transwiki imports.
	1.27	ImportSources	Called when reading from the $wgImportSources configuration variable
	1.16.0	ModifyExportQuery	Modify the query used by the exporter.
	1.15.0	WikiExporter::dumpStableQuery	Get the SELECT query for "stable" revisions dumps
	1.16.0	XmlDumpWriterOpenPage	Called at the end of XmlDumpWriter::openPage, to allow extra metadata to be added.
	1.16.0	XmlDumpWriterWriteRevision	Called at the end of a revision in an XML dump, to add extra metadata.
Diffs	1.14	AbortDiffCache	Can be used to cancel the caching of a diff
	1.17	ArticleContentOnDiff	Before showing the article content below a diff.
	1.29	DifferenceEngineAfterLoadNewText	called in DifferenceEngine::loadNewText() after the new revision's content has been loaded into the class member variable
	1.29	DifferenceEngineLoadTextAfterNewContentIsLoaded	called in DifferenceEngine::loadText() after the new revision's content has been loaded into the class member variable $differenceEngine->mNewContent but before checking if the variable's value is null.
	1.29	DifferenceEngineMarkPatrolledLink	Allow extensions to change the markpatrolled link, which is shown both on the diff header as well as on the bottom of a page, usually wrapped in a ‎<span> element which has class="patrollink".
	1.29	DifferenceEngineMarkPatrolledRCID	Allows extensions to possibly change the rcid parameter.
	1.29	DifferenceEngineNewHeader	Allows extensions to change the $newHeader variable, which contains information about the new revision, such as the revision's author, whether
	1.29	DifferenceEngineOldHeaderNoOldRev	Change the $oldHeader variable in cases when there is no old revision
	1.29	DifferenceEngineOldHeader	Allows extensions to change the $oldHeader variable, which contains information about the old revision, such as the revision's author, whether the revision was marked as a minor edit or not, etc.
	1.29	DifferenceEngineRenderRevisionAddParserOutput	Allows extensions to change the parser output. Return false to not add parser output via OutputPage's addParserOutput method.
	1.29	DifferenceEngineRenderRevisionShowFinalPatrolLink	An extension can hook into this hook point and return false to not show the final "mark as patrolled" link on the bottom of a page.
	1.29	DifferenceEngineShowDiffPageMaybeShowMissingRevision	called in DifferenceEngine::showDiffPage() when revision data cannot be loaded.
	1.29	DifferenceEngineShowDiffPage	Add additional output via the available OutputPage object into the diff view
	1.29	DifferenceEngineShowDiff	Allows extensions to affect the diff text which eventually gets sent to the OutputPage object.
	1.29	DifferenceEngineShowEmptyOldContent	Allows extensions to change the diff table body (without header) in cases when there is no old revision or the old and new revisions are identical.
	1.35	DifferenceEngineViewHeader	Called before displaying a diff
	1.21	DiffRevisionTools	(deprecated in 1.35) Override or extend the revision tools available from the diff view, i.e. undo, etc.
	1.35	DiffTools	Use this hook to override or extend the revision tools available from the diff view, i.e. undo, etc.
	1.7	DiffViewHeader	(deprecated in 1.35) Called before diff display
	1.25.0	GetDifferenceEngine	Allows custom difference engine extensions such as Special:MyLanguage/Extension:WikEdDiff.
	1.21	EditPageGetDiffContent	Allow modifying the wikitext that will be used in "Show changes". Note that it is preferable to implement diff handling for different data types using the ContentHandler facility.
	1.16	EditPageGetDiffText	(removed in 1.29) Allow modifying the wikitext that will be used in "Show changes"
	1.15	NewDifferenceEngine	Called when a new DifferenceEngine object is made.
	1.32	GetSlotDiffRenderer	Replace or wrap the standard SlotDiffRenderer for some content type.
Miscellaneous	1.19.0	AlternateUserMailer	Called before mail is sent so that mail could be logged (or something else) instead of using PEAR or PHP's mail().
	1.6.0	ArticleEditUpdatesDeleteFromRecentchanges	(deprecated in 1.35) Occurs before saving to the database.
	1.19	BacklinkCacheGetConditions	allows to set conditions for query when links to certain title
	1.19	BacklinkCacheGetPrefix	allows to set prefix for a spefific link table
	1.16	BeforeInitialize	Occurs before anything is initialized in MediaWiki::performRequest().
	1.36	BeforeRevertedTagUpdate	This hook is called before scheduling a RevertedTagUpdateJob.
	1.21.0	CategoryAfterPageAdded	Called after a page is added to a category
	1.21.0	CategoryAfterPageRemoved	Called after a page is removed from a category
	1.19.0	Collation::factory	Allows extensions to register new collation names, to be used with $wgCategoryCollation
	1.16	DatabaseOraclePostInit	(removed in 1.34) Called after initializing an Oracle database
	1.8.0	DisplayOldSubtitle	Allows extensions to modify the displaying of links to other revisions when browsing through revisions.
	1.17	ExtensionTypes	Called when generating the extensions credits, use this to change the tables headers.
	1.13	GetCacheVaryCookies	Get cookies that should vary cache options
	1.18	GetCanonicalURL	Allows to modify fully-qualified URLs used for IRC and e-mail notifications.
	1.18.0	GetDefaultSortkey	Allows to override what the default sortkey is, which is used to order pages in a category.
	1.21.0	GetDoubleUnderscoreIDs	hook for modifying the list of magic words
	1.6.0	GetFullURL	Used to modify fully-qualified URLs used in redirects/export/offsite data
	1.6.0	GetInternalURL	Used to modify fully-qualified URLs (useful for squid cache purging)
	1.17	GetIP	Modify the ip of the current user (called only once).
	1.6.0	GetLocalURL	Used to modify local URLs as output into page links
	1.19	GetLocalURL::Article	Allows to modify local URLs specifically pointing to article paths without any fancy queries or variants.
	1.19	GetLocalURL::Internal	Allows to modify local URLs to internal pages.
	1.35	GetMagicVariableIDs	Use this hook to modify the list of magic variables
	1.35	HtmlCacheUpdaterAppendUrls	This hook is used to declare extra URLs to purge from HTTP caches.
	1.35	HtmlCacheUpdaterVaryUrls	This hook is used to add variants of URLs to purge from HTTP caches.
	1.20	InfoAction	When building information to display on the action=info page
	1.13	InitializeArticleMaybeRedirect	Called when checking if title is a redirect.
	1.18	InterwikiLoadPrefix	(deprecated in 1.36) This hook is called when resolving whether a given prefix is an interwiki or not.
	1.18	IRCLineURL	When constructing the URL to use in an IRC notification.
	1.19	Language::getMessagesFileName	Use to change the path of a localisation file.
	1.6	LanguageGetMagic	(removed in 1.33) Use this to define synonyms of magic words depending of the language.
	1.18	LanguageGetTranslatedLanguageNames	Provide translated language names.
	1.22.0	LanguageLinks	Manipulate a page's language links.
	1.14.0	LinkBegin	(removed in 1.36) Used when generating internal and interwiki links in Linker::link()
	1.14.0	LinkEnd	(removed in 1.36) Used when generating internal and interwiki links in Linker::link(), just before the function returns a value.
	1.12	LinksUpdate	At the beginning of LinksUpdate::doUpdate() just before the actual update
	1.21	LinksUpdateAfterInsert	Occurs right after new links have been inserted into the links table
	1.12	LinksUpdateComplete	At the end of LinksUpdate::doUpdate() when updating has completed
	1.11	LinksUpdateConstructed	At the end of LinksUpdate() is construction.
	1.10.1	LoadExtensionSchemaUpdates	Fired when MediaWiki is updated to allow extensions to register updates for the database schema
	1.24	LocalisationCacheRecacheFallback	Called for each language when merging fallback data into the cache.
	1.16	LocalisationCacheRecache	Called when loading the localisation data into cache
	1.23	LocalisationChecksBlacklist	When fetching the blacklist of localisation checks.
	1.24	LocalisationIgnoredOptionalMessages	args = array &$ignoredMessageKeys, array &$optionalMessageKeys
	1.6.0	MagicWordwgVariableIDs	(deprecated in 1.35) Tells MediaWiki that one or more magic word IDs should be treated as variables.
	1.18	MaintenanceRefreshLinksInit	Before executing the refreshLinks.php maintenance script.
	1.33	MaintenanceUpdateAddParams	allow extensions to add params to the update.php maintenance script.
	1.23	MathMLChanged	Is called before the MathML property is changed can be used e.g. for compression, normalization or introduction of custom hyperlinks etc.
	1.12.0	MediaWikiPerformAction	Override MediaWiki::performAction()
	1.32	MediaWikiPHPUnitTest::endTest	Occurs when a MediaWiki PHPUnit test has ended.
	1.32	MediaWikiPHPUnitTest::startTest	Occurs when a MediaWiki PHPUnit test has started.
	1.27.0	MediaWikiServices	Called when a global MediaWikiServices instance is initialised.
	1.23	MessageCache::get	Allows changing a message key, to customize it before the translation is accessed
	1.15	MessageCacheReplace	When a message page is changed. Useful for updating caches.
	1.5.7	MessagesPreLoad	Occurs when loading a message from the database
	1.24	MimeMagicGuessFromContent	Allows MW extensions guess the MIME by content.
	1.24	MimeMagicImproveFromExtension	Allows MW extensions to further improve the MIME type detected by considering the file extension.
	1.24	MimeMagicInit	Before processing the list mapping MIME types to media types and the list mapping MIME types to file extensions. As an extension author, you are encouraged to submit patches to MediaWiki's core to add new MIME types to mime.types.
	1.13	NormalizeMessageKey	(removed in 1.27) Allows extensions to change what system message will be displayed on a page
	1.13	OpenSearchUrls	Called when constructing the OpenSearch description XML. Hooks can alter or append to the array of URLs for search & suggestion formats.
	1.25	OpportunisticLinksUpdate	allows performing updates when a page is re-rendered
	1.20	ParserTestGlobals	Allows to define globals for parser tests.
	1.6.0	ParserTestParser	called when creating a new instance of Parser for parser tests
	1.10	ParserTestTables	(deprecated in 1.36) alter the list of tables to duplicate when parser tests are run. Use when page save hooks require the presence of custom tables to ensure that tests continue to run properly.
1.12	PrefixSearchBackend	(deprecated in 1.27) Override the title prefix search used for OpenSearch and AJAX search suggestions.
1.25	PrefixSearchExtractNamespace	Called if core was not able to extract a namespace from the search string so that extensions can attempt it.
1.10	RawPageViewBeforeOutput	called before displaying a page with action=raw. Returns true if display is allowed, false if display is not allowed.
1.30	RecentChangesPurgeRows	Called when old recentchanges rows are purged, after deleting those rows but within the same transaction.
1.27	RequestHasSameOriginSecurity	Called to determine if the request is somehow flagged to lack same-origin security.
1.8.0	RecentChange_save	Called after a "Recent Change" is committed to the DB
1.16	SearchableNamespaces	An option to modify which namespaces are searchable.
1.21	SearchAfterNoDirectMatch	If there was no match for the exact result. This runs before lettercase variants are attempted, whereas SearchGetNearMatch runs after.
1.28	SearchDataForIndex	Allows to provide custom content fields when indexing a document.
1.16	SearchGetNearMatchBefore	Perform exact-title-matches in "go" searches before the normal operations.
1.16	SearchGetNearMatchComplete	A chance to modify exact-title-matches in "go" searches.
1.12	SearchGetNearMatch	An extra chance for exact-title-matches in "go" searches
1.28	SearchIndexFields	Add fields to search index mapping
1.20	SearchResultInitFromTitle	Set the revision used when displaying a page in search results.
1.35	SearchResultProvideDescription	Called when generating search results in order to fill the "description" field in an extension.
1.35	SearchResultProvideThumbnail	This hook is called when generating search results in order to fill the thumbnail field in an extension.
1.28	SearchResultsAugment	Allows extension to add its code to the list of search result augmentors.
1.25	SecondaryDataUpdates	(deprecated in 1.32) Allows modification of the list of DataUpdates to perform when page content is modified.
1.24	SelfLinkBegin	called when rendering a self link on a page
1.23	SendWatchlistEmailNotification	Can be used to cancel watchlist email notifications (enotifwatchlist) for an edit.
1.14	SetupAfterCache	Called in Setup.php, after cache objects are set
1.15	SoftwareInfo	Called by Special:Version for returning information about the software.
1.18	TestCanonicalRedirect	Called when about to force a redirect to a canonical URL for a title when we have no other parameters on the URL.
1.22.0	TitleSquidURLs	To modify/provide alternate URLs to send HTTP PURGE requests.
1.30.0	UnitTestsAfterDatabaseSetup	Called right after MediaWiki's test infrastructure has finished creating/duplicating core tables for unit tests.
1.30.0	UnitTestsBeforeDatabaseTeardown	Called right before MediaWiki's test infrastructure begins tearing down tables for unit tests.
1.17.0	UnitTestsList	Add tests that should be run as part of the unit test suite.
1.4.0	UnknownAction	(removed in 1.32) Before MediaWiki 1.19, used to add new query-string actions.
1.24.0	UserMailerChangeReturnPath	Called to generate a VERP return address when UserMailer sends an email, with a bounce handling extension.
1.29	WatchedItemQueryServiceExtensions	Add a WatchedItemQueryServiceExtension
1.19	WebRequestPathInfoRouter	While building the PathRouter to parse the REQUEST_URI.
1.22	WebResponseSetCookie	Use to modify the cookie being set from WebResponse::setcookie().
1.20	wfShellWikiCmd	Called when generating a shell-escaped command line string to run a cli script.
1.6.0	wgQueryPages	Runs for every Special page that extends the QueryPage class (fired when including the file QueryPage.php). It is only useful in maintenance/updateSpecialPages.php and in QueryPage Api.

Alphabetical list of hooks

For a complete list of hooks, use the category , which should be kept more up to date.

See also

• $wgHooks
• Category:Hook extensions
• Manual:Tag extensions
• Manual:Parser functions
• Hooks.md — specification of the hooks system
• List of hook interfaces in MediaWiki Core
• Extension:Examples — contains examples of hooks
• mw.hook — the JavaScript/front-end system of hooks