View source for Extension:VisualEditor

{{Languages|:Extension:VisualEditor}}
{{DoNotTranslate}}<!-- <languages/> should not be enabled until the extension is fixed to work with Parsoid/VE. See [[Special:Diff/989631]] and [[Special:Diff/1081067]] -->
{{Extension
| image = VisualEditor-logo.svg
| status = stable
| type1 = page action
| type2 = extended syntax
| type3 = beta feature
| type4 = skin
| description = Allows for editing pages as rich content
| download = {{WikimediaDownload|VisualEditor|phab=EVED}}
| needs-updatephp = No
| readme = [[git:mediawiki/extensions/VisualEditor/+/master/README.md|README]]
| help = {{ll|Help:VisualEditor/User guide}}
| phabricator = visualeditor
| version = continuous updates
| latest release date = 
| translate = ext-visualeditor-0-all
| vagrant-role = visualeditor
| compatibility policy = rel
}}

The '''VisualEditor''' extension allows for editing pages as rich content. It is based around a JavaScript library, also called "VisualEditor", that can potentially be used outside of MediaWiki as well. This page covers instructions for installing and configuring the VisualEditor extension. For help on using it, see {{ll|Help:VisualEditor/User guide}}. For information on the development of the extension and the library, see {{ll|VisualEditor}}.
__TOC__
== Installation ==
{{Bundled|1.35}}
===Current versions (1.35 and above)===
The extension is bundled with MediaWiki core. It should already be present in the Extensions folder.

Add the following line of code to LocalSettings.php.

<code>wfLoadExtension( 'VisualEditor' );</code>

Run an {{ll|Manual:update.php|update}}.

{{done}}

===Obsolete versions (pre-1.35)===

{{ExtensionInstall
|repo-name=VisualEditor
|git-submodule=1
|registration=required
}}

== Download ==
=== For the General User ===

If you downloaded the MediaWiki tarball, you do not need to download this extension.

=== If you are using Git ===

{{note}}
* VisualEditor’s master branch contains the latest code, as used at Wikimedia. This code is potentially slightly buggy or unstable, but is likely to have fewer bugs and more features than old builds.
* '''The master branch requires alpha builds of MediaWiki''' and will not work with the older, official releases of MediaWiki like {{MW legacy lts branch number}}; for that, use the <code>{{MW legacy lts release git}}</code> branch (command: {{Inline-code|git clone -b REL1_39 https://gerrit.wikimedia.org/r/mediawiki/extensions/VisualEditor.git|lang=bash}}).
* The {{Inline-code|git submodule update --init|lang=bash}} command is vital, as VisualEditor MediaWiki extension needs the core VisualEditor submodule to work. '''If you do not use this command, VisualEditor will fail to work'''.
* See {{ll|Parsoid#Development}} for details on linking an alpha build of the Parsoid library up to VisualEditor; the latest version of VisualEditor '''will''' need a development version of Parsoid as well.  '''You must follow the instructions on the {{ll|Parsoid}} page to configure Parsoid if you are installing VisualEditor from git, or using an alpha release of 1.36!'''  If you do not, VisualEditor will fail to work.

== Skin compatibility ==
Though only tested and supported with {{ll|Skin:Vector|nsp=0}}, {{ll|Skin:MonoBook|nsp=0}}, and {{ll|Skin:Minerva Neue|nsp=0}}, VisualEditor is known to also be compatible with the following skins:
* {{ll|Skin:Timeless|nsp=0}}
* {{ll|Skin:Chameleon|nsp=0}}
* {{ll|Skin:Apex|nsp=0}}
* {{ll|Skin:Poncho|nsp=0}}
* {{ll|Skin:Cosmos|nsp=0}}
* {{ll|Skin:Modern|nsp=0}}
* {{ll|Skin:Medik|nsp=0}}
* {{ll|Skin:Citizen|nsp=0}}
There are many other skins that are also not officially supported but should work; it should be compatible with any skin that uses the required HTML structure – see '''{{ll|Extension:VisualEditor/Skin requirements|nsp=0}}'''. Some fiddling with skin stylesheets might be necessary to make everything look nice. It will load on any skin if it matches the feature detection.

== Setting up VisualEditor ==
{{Ambox
| text = You should not need to change almost any of the configuration below, unless you have an unusual installation of MediaWiki.
}}

=== Enabling VisualEditor for users ===
The following optional configurations can be used:

<syntaxhighlight copy="" lang="php">
// Optional: Set VisualEditor as the default editor for logged-out users
// otherwise they will have to switch to VE
$wgDefaultUserOptions['visualeditor-editor'] = "visualeditor";

// Optional: Don't allow users to disable it
$wgHiddenPrefs[] = 'visualeditor-enable';

// Optional: Enable VisualEditor's experimental code features
$wgDefaultUserOptions['visualeditor-enable-experimental'] = 1;

// Activate ONLY the 2017 wikitext editor by default
$wgDefaultUserOptions['visualeditor-autodisable'] = true;
$wgDefaultUserOptions['visualeditor-newwikitext'] = 1;
</syntaxhighlight>
Other extensions which load plugins for VE can be loaded before or after VE; the plugins should work either way.

=== Changing namespaces where VisualEditor is available ===
By default, VisualEditor is enabled for the namespaces "User", "File", "Category", and [[Special:MyLanguage/Manual:$wgContentNamespaces|content namespaces]] (contains "Main" by default). It is however possible to add or remove namespace using the English language canonical names defined for the respective namespaces such as e.g. "Project", "Talk" etc. Additional custom namespaces use the names used to create them.

<syntaxhighlight copy="" lang="php">
// Enable for the meta namespace, disable for the "File" namespace and enable for the "Extra", the latter being a custom namespace
$wgVisualEditorAvailableNamespaces = [
    'Project' => true,
    'File' => false,
    'Extra' => true
];
</syntaxhighlight>

=== Apache configuration concerns ===

==== Short URLs on Apache ====
If you are using non-standard {{ll|Short URLs on Apache|short URLs}} such as <nowiki>"https://wiki.example.org/Page_title"</nowiki> on Apache, you need to {{ll|Extension:VisualEditor/Apache rewrite rules for short URLs|adapt the rewrite rules}} for the web server.

VisualEditor will display some broken links if the wiki is not configured with Short Urls. See {{phab|T328337}}.

==== Allowing VisualEditor on page titles containing slashes ====
If you are serving MediaWiki from apache2, you will need to add the following to your top level server configuration (often a <code>&lt;VirtualHost></code> section in <code>/etc/apache2/sites-enabled/000-default.conf</code> or similar):
<syntaxhighlight copy="" lang="apacheconf">
AllowEncodedSlashes NoDecode
</syntaxhighlight>

If you do not, then VisualEditor will complain that "Revision IDs returned by the server do not match" or simply "Error contacting the Parsoid/RESTBase server (HTTP 404)" when editing a page title containing a slash, for example a subpage. See {{Phabricator|268953}} and the [https://httpd.apache.org/docs/2.4/mod/core.html#allowencodedslashes apache documentation] for more information.

If the Apache server happens to be behind a Nginx proxy then its <code>proxy_pass</code> stanza should make use of the <code>$request_uri</code> parameter (cf. [https://stackoverflow.com/a/20514632 discussion] on StackOverflow).

==== Servers with multiple virtual sites ====
{{Note
| 1 = Parsoid is served in production using {{ll|Extension:MediaWikiFarm}}.  Running Parsoid on multiple virtual sites using other mechanisms is untested; the instructions below have not been tested.
}}

If Apache2 is configured with multiple virtual sites, Parsoid is (in standard configuration) only able to access the default site.  To check for this problem, run <code>curl '<nowiki>[http://your-wiki-base-url</nowiki>]/rest.php/v1/page/Main_Page'</code> on the server, or run <code>curl '<nowiki>[https://your-wiki-base-url</nowiki>]/rest.php/v1/page/Main_Page'</code> ensuring the URL matches the SSL certificate used on the server.

If the response contains the main page of your wiki then you don't have the problem, but if it doesn't, you may need to configure a host alias that Parsoid can use:

Look at the apache2 configuration file for the virtual server hosting the wiki, near the top of the file there should be a line like: 
<blockquote><code><nowiki><VirtualHost *:80></nowiki></code></blockquote>
If the '*' is present, then the alias can be to localhost, if there is an IP address replacing the '*' then the alias must be to that IP address. In the same file add a line: <blockquote><code>ServerAlias my_wiki_alias</code></blockquote>

In the hosts file of the server (/etc/hosts on Ubuntu), add a route for my_wiki_alias, either for 127.0.0.1 (if the apache2 virtual server configuration had the '*' above, else to the IP address from the apache2 virtual server configuration.

Now set the hostname in {{wg|Server}} to <code>protocol://my_wiki_alias</code> on the host running VisualEditor.

=== Linking with a separate Parsoid ===
By default VisualEditor is automatically configured to talk to a Parsoid service running on the same host (and on the same port).  '''You should not need to change this in most cases!'''

Some cases when you do need to change the URL of Parsoid:
* Your MediaWiki server is behind a proxy (different remote and local port).
* Your MediaWiki is running inside a docker container with port mapping.
* You want to run Parsoid on a dedicated host or cluster. 

If you need to do this, add the following code to your <code>LocalSettings.php</code> to specify the URL for your Parsoid instance:
<syntaxhighlight copy lang="php">
$wgVirtualRestConfig['modules']['parsoid'] = array(
    // URL to the Parsoid instance.
    // You should change $wgServer to match the non-local host running Parsoid
    // Note! This is a server to server URL (it must be valid within your VM/container)
    // For a VM or docker this will probably be correct:
    // 'url' => "http://localhost/rest.php",
    'url' => $wgServer . $wgScriptPath . '/rest.php',
    // Parsoid "domain", see below (optional, rarely needed)
    // 'domain' => 'localhost',
);
</syntaxhighlight>

Note that you do not need to the initialise the {{Wg|VirtualRestConfig}} array anywhere in LocalSettings.

Parsoid's <code>domain</code> setting here must match the host portion of {{Wg|Server}} on the host running the Parsoid service.

If you do set any property in {{Phpi|$wgVirtualRestConfig['modules']['parsoid']}} '''you will have to {{ll|Parsoid#Linking a developer checkout of Parsoid|manually install Parsoid}} or VisualEditor will not work!'''

==== Linking with Parsoid in private wikis via forwarding cookies to Parsoid ====
In a private wiki, you should do this:{{Warning|1={{strong|Potential security vulnerability.}} Enabling this setting on an HTTP-served private wiki will transmit cookie headers, including authentication data, unencrypted to Parsoid. Enable only if absolutely necessary and only with full understanding of the associated security risks.}}

This is the default configuration for VisualEditor if [[gerrit:q/I0b958e8b75c04e4a27f50f91276be221a5b1404d|not everyone is allowed to read every page]], as such '''the below should not be required in most cases'''.

<syntaxhighlight copy lang="php">
// Forward users' Cookie: headers to Parsoid. Required for private wikis (login required to read).
// If the wiki is not private (i.e. $wgGroupPermissions['*']['read'] is true) this configuration
// variable will be ignored.
//
// WARNING: ONLY enable this on private wikis and ONLY IF you understand the SECURITY IMPLICATIONS
// of sending Cookie headers to Parsoid over HTTP.
$wgVirtualRestConfig['modules']['parsoid']['forwardCookies'] = true;
</syntaxhighlight>

If you do set any property in <code>{{Phpi|$wgVirtualRestConfig['modules']['parsoid']}}</code> '''you will have to {{ll|Parsoid#Linking a developer checkout of Parsoid|manually install Parsoid}} or VisualEditor will not work!'''

== Quick configuration guide ==
<div class="noresize">
{| class="wikitable"
! Feature
! Beta Features opt-in state
! Enabled for all to opt-in
! Enabled for all to opt-out
! Enabled for all without opt-out
|-
! Visual mode
| {{MW version-inline|MW 1.36+}}<syntaxhighlight copy lang="php">
$wgVisualEditorEnableBetaFeature = true;
</syntaxhighlight>{{MW version-inline|MW <1.36}}

''Beta Feature shown by default; disable using:''<syntaxhighlight copy lang="php">
$wgHiddenPrefs[] = 'visualeditor-enable';
</syntaxhighlight>
| <syntaxhighlight copy lang="php">
$wgDefaultUserOptions['visualeditor-autodisable'] = true;
</syntaxhighlight>
| ''Enabled by default''
| ''As in "Enabled for all to opt-out" plus:''<syntaxhighlight copy lang="php">
$wgHiddenPrefs[] = 'visualeditor-enable';
</syntaxhighlight>
|-
! Wikitext mode
| <syntaxhighlight copy lang="php">
$wgVisualEditorEnableWikitextBetaFeature = true;
</syntaxhighlight>
| <syntaxhighlight copy lang="php">
$wgVisualEditorEnableWikitext = true;
</syntaxhighlight>
| <syntaxhighlight copy lang="php">
$wgVisualEditorEnableWikitext = true;
$wgDefaultUserOptions['visualeditor-newwikitext'] = 1;
</syntaxhighlight>
| ''As in "Enabled for all to opt-out" plus:''<syntaxhighlight copy lang="php">
$wgHiddenPrefs[] = 'visualeditor-newwikitext';
</syntaxhighlight>
|-
! Single edit tab
| ''Not a supported configuration.''
| <syntaxhighlight copy lang="php">
$wgVisualEditorUseSingleEditTab = true;
$wgDefaultUserOptions['visualeditor-tabs'] = 'multi-tab';
</syntaxhighlight>
| <syntaxhighlight copy lang="php">
$wgVisualEditorUseSingleEditTab = true;
</syntaxhighlight>Default edit tab behaviour will be to remember the last editor, and open with the wikitext editor for first edit; if you want it to be the visual editor, also add:<syntaxhighlight copy lang="php">
$wgDefaultUserOptions['visualeditor-editor'] = 'visualeditor';
</syntaxhighlight>
| ''As in "Enabled for all to opt-out" plus:''<syntaxhighlight copy lang="php">
$wgHiddenPrefs[] = 'visualeditor-tabs';
</syntaxhighlight>
|-
! Visual diffs on history pages
| <syntaxhighlight copy lang="php">
$wgVisualEditorEnableDiffPageBetaFeature = true;
</syntaxhighlight>
| ''Not a supported configuration.''
| ''Not a supported configuration.''
| <syntaxhighlight copy lang="php">
$wgVisualEditorEnableDiffPage = true;
</syntaxhighlight>
|}
</div>

== Complete list of configuration options ==
Each configuration option is shown without the <code>$wgVisualEditor</code> prefix for brevity; replace the '…' when using.
<div class="noresize">
{| class="wikitable"
! Option
! Default value<!-- As of MW1.30.0-wmf2 -->
! Useful for…
! Documentation
|-
| <code>…PluginModules</code>
| <syntaxhighlight lang="json">
[]
</syntaxhighlight>
| Extension developers
| Array of ResourceLoader module names (strings) that should be loaded when VisualEditor is loaded. Other extensions that extend VisualEditor should add to this array.{{Warning|1=When removing a module on a production site (''e.g.'' Wikimedia), first remove it from this array, wait for the change to propagate, and only then remove the module code and module registration. Otherwise there may be a period of time during which VisualEditor depends on a module that no longer exists.}}
|-
| <code>…PreloadModules</code>
| <syntaxhighlight copy lang="json">
[
    "site",
    "user"
]
</syntaxhighlight>
| Extension developers
| Array of ResourceLoader module names (strings) that should be loaded before VisualEditor is loaded. Other extensions that extend VisualEditor and need to set up their environment before loading should add to this array.{{Warning|1=When removing a module on a production site (''e.g.'' Wikimedia), first remove it from this array, wait for the change to propagate, and only then remove the module code and module registration. Otherwise there may be a period of time during which VisualEditor depends on a module that no longer exists.}}
|-
| <code>…PreferenceModules</code>
| <syntaxhighlight copy lang="json">
{
	"visualeditor-enable-experimental": "ext.visualEditor.experimental"
}
</syntaxhighlight>
| Extension developers
| Associative array of ResourceLoader module names (strings) that should be loaded when VisualEditor is loaded '''if''' the current user has a preference set. Other extensions that extend VisualEditor should add to this array if they want their addition to be opt-in or opt-out. Keys are preference names, values are ResourceLoader module names. 

Remember to also set defaults in <code>$wgDefaultUserOptions</code>!
|-
| <code>…ParsoidAutoConfig</code>
| <syntaxhighlight lang="json">
true
</syntaxhighlight>
| Sysadmins
| Enables auto-configuration of the bundled version of the Parsoid REST API.  Set to <code>false</code> if you have an unusual Parsoid configuration and want to manually configure it.
|-
| <code>…RestbaseURL</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| URL to use to access the main RESTBase call. The page name will be appended directly to this value, so this needs to be set to something like '<code>https://en.wikipedia.org/api/rest_v1/page/html/</code>' <u>including</u> the trailing slash.

If this is set, the page HTML will be requested from RESTBase. If this is not set, the page HTML will be requested from the API, which will send an HTTP request to Parsoid or to RESTBase if available.
|-
| <code>…FullRestbaseURL</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| URL to use to access the rest of RESTBase. The page name will be appended directly to this value, so this needs to be set to something like '<code>https://en.wikipedia.org/api/rest_</code>' <u>excluding</u> the trailing slash.
|-
| <code>…AllowLossySwitching</code>
| <syntaxhighlight lang="json">
true
</syntaxhighlight>
| Sysadmins
| Whether to allow switching from wikitext to visual editor even if doing so may cause {{ll|VisualEditor/Design/Software overview#Dirty-diffs|dirty diffs}}.
|-
| <code>…SerializationCacheTimeout</code>
| <syntaxhighlight lang="json">
3600
</syntaxhighlight>
| Sysadmins
| Serialization cache timeout, in seconds
|-
| <code>…AvailableNamespaces</code>
| <syntaxhighlight copy lang="php">
[
    "User" => true,
    "File" => true,
    "Category" => true,
    "_merge_strategy" => "array_plus"
]
</syntaxhighlight>
| Sysadmins
| Namespaces in which to enable VisualEditor (mapped from namespace canonical name to a boolean flag), on top of <code>$wgContentNamespaces</code>.
|-
| <code>…AvailableContentModels</code>
| <syntaxhighlight copy lang="php">
[
    "wikitext" => "article",
    "_merge_strategy" => "array_plus"
]
</syntaxhighlight>
| Extension developers
| Content models in which to enable VisualEditor (mapped from content model name to a boolean flag).
|-
| <code>…UseChangeTagging</code>
| <syntaxhighlight lang="json">
true
</syntaxhighlight>
| Sysadmins
| Whether to put a {{ll|Manual:Tags|change tag}} on every edit made with VisualEditor.
|-
| [[#Integration of "2017 wikitext editor"|<code>…EnableWikitext</code>]]
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to enable the {{ll|2017 wikitext editor|wikitext source mode}} inside VisualEditor.
|-
| <code>…EnableDiffPage</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to enable the {{ll|VisualEditor/Diffs|visual diff}} function on the history special page.
|-
| <code>…EnableDiffPageBetaFeature</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to allow users to enable the {{ll|VisualEditor/Diffs|visual diff}} function on the history special page as a beta feature.
|-
| <code>…EnableVisualSectionEditing</code>
| <syntaxhighlight lang="json">
mobile
</syntaxhighlight>
| Sysadmins
| Whether to allow users to enable the section editing.
|-
| <code>…UseSingleEditTab</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to use only one edit tab, switching back and forth, or add a dedicated VisualEditor edit tab next to the existing one.
|-
| <code>…SingleEditTabSwitchTime</code>
| <syntaxhighlight lang="json">
20160101000000
</syntaxhighlight>
| Sysadmins
| From what timestamp to warn existing editors that the installation has switched from two edit tabs to one. In general you should ignore this.
|-
| <code>…TabPosition</code>
| <syntaxhighlight lang="json">
'before'
</syntaxhighlight>
| Sysadmins
| If showing two edit tabs, where to put the VisualEditor edit tab in relation to the system (or WikiEditor) one:
* 'before': put it right before the old edit tab
* 'after': put it right after the old edit tab
|-
| <code>…TabMessages</code>
| <syntaxhighlight copy lang="json">
{
	"edit": null,
	"editsource": "visualeditor-ca-editsource",
	"create": null,
	"createsource": "visualeditor-ca-createsource",
	"editlocaldescriptionsource": "visualeditor-ca-editlocaldescriptionsource",
	"createlocaldescriptionsource": "visualeditor-ca-createlocaldescriptionsource",
	"editsection": null,
	"editsectionsource": "visualeditor-ca-editsource-section"
}
</syntaxhighlight>
| Sysadmins
| Configuration of what messages to use for the various kinds of edit tab users can see, if showing two edit tabs:

'<strong>edit</strong>' – i18n message key to use for the VisualEditor edit tab; if <code>null</code>, the default edit tab caption will be used; the '<code>visualeditor-ca-ve-edit</code>' message is available for this.

'<strong>editsource</strong>' – i18n message key to use for the old edit tab; if <code>null</code>, the tab's caption will not be changed

'<strong>create</strong>' – i18n message key to use for the VisualEditor create tab; if <code>null</code>, the default create tab caption will be used; the '<code>visualeditor-ca-ve-create</code>' message is available for this

'<strong>createsource</strong>' – i18n message key to use for the old create tab; if <code>null</code>, the tab's caption will not be changed

'<strong>editlocaldescriptionsource</strong>' – i18n message key to use for the old edit tab on pages for files in foreign repos; if <code>null</code>, tab's caption will not be changed

'<strong>createlocaldescriptionsource</strong>' – i18n message key to use for the old create tab on pages for files in foreign repos; if <code>null</code>, tab's caption will not be changed

'<strong>editsection</strong>' – i18n message key to use for the VisualEditor section edit link; if <code>null</code>, the default edit section link caption will be used

'<strong>editsectionsource</strong>' – i18n message key to use for the source section edit link; if <code>null</code>, the link's caption will not be changed
|-
| <code>…AutoAccountEnable</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to enable VisualEditor for every new account.

This allows you to keep the '<code>visualeditor-enable</code>' preference disabled by default, but still have VisualEditor available for new logged-in users (by setting this to <code>true</code>).
|-
| <code>…DisableForAnons</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to disable VisualEditor for non-logged-in users

This allows you to enable the '<code>visualeditor-enable</code>' preference by default, but still disable VisualEditor for logged-out users (by setting this to <code>true</code>).
|-
| <code>…TransitionDefault</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| For wikis planning to use the '<code>visualeditor-betatempdisable</code>' preference to auto-opt-out existing users whilst enabling by default for all existing users, whether to start recording explicit opt-outs against implicit ones. 
|-
| <code>…ShowBetaWelcome</code>
| <syntaxhighlight lang="json">
true
</syntaxhighlight>
| Sysadmins
| Whether to show the "welcome to the beta" dialog the first time a user uses VisualEditor
|-
| <code>{{nowrap|…NewAccountEnableProportion}}</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins running user analytics
| Whether to enable VisualEditor for a proportion (Egyptian fraction) of all new accounts based on userID.
|-
| <code>…FeedbackTitle</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| Whether to enable the MediaWiki feedback tool inside the help menu of VisualEditor. If enabled, the title of the page at which to point the MediaWiki feedback tool.
|-
| <code>…FeedbackAPIURL</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| Sysadmins
| If set, the API of the remote wiki at which to point the MediaWiki feedback tool.
|-
| <code>…SkinToolbarScrollOffset</code>
| <syntaxhighlight lang="json">
[]
</syntaxhighlight>
| Skin developers
| An array of skin names mapped to pixel values to which to set the toolbar scroll offsets.
|-
| <code>…BrowserUnsupportedList</code>
| 
| VisualEditor developers
| List of browsers with which VisualEditor is incompatible. See <code>jquery.Client</code> for specification. If the user's browser is matched, VisualEditor will refuse to load.

'''Firefox''' – There is a wikilink corruption (<code><nowiki>[[./]]</nowiki></code>) bug in Firefox 14 and below ({{T|52720}}) which prevent wider availability.

'''Safari''' – Older versions of Safari suffered from corruption issues from various old browser plugins.

'''Opera''' – Below version 12, Opera was untested, and as its user base is almost non-existent anyway it's blocked.

'''Internet Explorer''' – At or below version 9, there are various incompatibilities in layout and feature support. Versions 10 and 11 should work correctly.

Not listed independently, because it's inherited from MediaWiki itself, '''Android''' at 3.x and below "support" CE but don't trigger keyboard input or have other issues, making it useless for users.
|-
| <code>…EnableTocWidget</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| VisualEditor developers
| Whether to enable the (currently experimental) Table Of Contents widget
|-
| <code>…RebaserURL</code>
| <syntaxhighlight lang="json">
false
</syntaxhighlight>
| VisualEditor developers
| URL to use to access the experimental rebaser technology. If false, the technology isn't loaded.
|}
</div>

=== Related configuration parameters ===
See also {{ll|Upload dialog#Configuration (for wiki sysadmins)}} for information about configuring the drag-and-drop/copy&paste functionality for uploading media files through VisualEditor.

== Integration of "2017 wikitext editor" ==
To enable the so-called "2017 wikitext editor", follow the instructions for '''Wikitext mode''' in the {{§l||Quick configuration guide}}.

It is also possible to enable wikitext syntax highlighting for this editor; to do this, you must install the {{ll|Extension:CodeMirror|CodeMirror}} extension.

== Rich template forms ==
{{ll|Extension:TemplateData}} allows the addition of template information, making templates easier to insert with the VisualEditor

== Improved citation tool ==
Citations can be improved by configuring the {{ll|VisualEditor/Citation tool|citation tool}}, and also by setting up {{ll|Citoid}}.

== Hooks ==
As of 2023, Visual Editor sets around 10 JavaScript hooks and 3 PHP hooks that are listed at {{ll|VisualEditor/Hooks}}.

== Troubleshooting ==
; All templates appear as puzzle icons instead of displaying its contents
: Check [[Extension talk:VisualEditor/2019#h-Every_template_on_a_page_displayed_as_puzzle_icon-2019-09-06T12:29:00.000Z]]

; Docker<nowiki>:</nowiki> Error contacting the Parsoid/RESTBase server (curl error<nowiki>:</nowiki> 7)
: Ensure that the mediawiki container name does not equal to the domain the wiki is running on. If both names are equal, the api will try to connect to the domain the wiki is running on, but only receive the local ip of the container. This will cause errors when ssl is enabled.

;Error contacting the Parsoid/RESTBase server (curl error<nowiki>:</nowiki> 7) Couldn't connect to server
: Ensure that the mediawiki native hostname does not equal to the domain the wiki is running on. If both names are equal, the api will try to connect to the domain the wiki is running on, but will have difficulty resolving the domain.

; Error contacting the Parsoid/RESTBase server<nowiki>:</nowiki> (curl error<nowiki>:</nowiki> 60) Peer certificate cannot be authenticated with given CA certificates
: You may be using a self-signed SSL certificate. Workaround unknown.

; Error contacting the Parsoid/RESTBase server<nowiki>:</nowiki> http-bad-status
:* When editing subpages on Apache, <code>AllowEncodedSlashes NoDecode</code> must be added in the VirtualHost section of the wiki ({{T|268953}}).
:* On a HTTP Auth protected wiki, you must allow local access via an allow / geo block in your Apache/Nginx config
:* On a private wiki, see ''"parsoidserver-http-bad-status<nowiki>:</nowiki> 401"'', below

; Error contacting the Parsoid/RESTBase server (HTTP 400)
:* If you are using a Short URL config, check your Nginx/Apache config for <code>/rest.php/?$query_string</code> block – see respective {{ll|Manual:Short_URL#Guides}}
:* An unresolved error for some users. ([[Extension talk:VisualEditor/2021#h-Inconsitent_error_"Error_contacting_the_Parsoid/RESTBase_server_(HTTP_400)"-2021-07-05T13:51:00.000Z]])

; Error contacting the Parsoid/RESTBase server (HTTP 403)
:* Caused by the 'writeapi' right being revoked (or not granted). Check your LocalSettings.php and remove any overrides for this right. ({{T|265043}})
:* Or caused by ModSecurity (or possibly another WAF). Request your hosting service provider to whitelist the security rules that were being triggered by your site. A rule known to cause this is the "missing content-length" check enabled. This rule checks for 'suspicious' but protocol valid behavior. It triggers on multipart POST's and should not be enabled ({{T|265043#6866940}})

; Error contacting the Parsoid/RESTBase server (HTTP 404)
: Possible reasons for this problem:
:* Caused by ModSecurity (or possibly another WAF). Request your hosting service provider to whitelist the security rules that were being triggered by your site.
:* When the web server is Apache, <code>AllowEncodedSlashes NoDecode</code> must be added in the VirtualHost section of the wiki ({{T|261921}}).
:* Possibly Parsoid is not loaded when using default configuration (local Parsoid, no RestBase). Add to LocalSettings.php: {{phpi|wfLoadExtension( 'Parsoid', 'vendor/wikimedia/parsoid/extension.json' );}}.
:* If you are using a proxy server or a docker port mapping you will need to set your local url in {{phpi|$wgVirtualRestConfig['modules']['parsoid']}} (see: [[#Linking with Parsoid in private wikis via forwarding cookies to Parsoid]]).
:* Caused by VisualEditor for MW 1.35 and later due to insufficient rewrite rules in case of non-standard short URLs ({{T|270376}}). See {{ll|Extension:VisualEditor/Apache rewrite rules for short URLs|Apache rewrite rules for short URLs}} for the solution.
:* If using {{ll|Manual:Short_URL|short URLs}}, place "{{phpi|RewriteCond %{HTTP_USER_AGENT} !^(VisualEditor)}}" just above "{{phpi|RewriteCond %{DOCUMENT_ROOT}%{REQUEST_URI} !-f}}".
:* If you have installed MediaWiki using the Debian <code>mediawiki</code> package, and if the file <code>rest.php</code> is not in your installation path, you are probably missing some new symbolic links (eventually evaluate the command <code>ln -s /var/lib/mediawiki/* .</code> from the installation path to install only the missing ones. In this case, you can ignore the errors about links you aready have)

; Error contacting the Parsoid/RESTBase server (HTTP 415)
: If you're running a private wiki, you might be encountering bug {{T|268277}}.
: If you're running a secure site (SSL), but {{wg|Server}} is set to a protocol-relative URL (<code>//wiki.example.org</code>), you might be encountering bug {{T|299175}}.

; Error contacting the Parsoid/RESTBase server (HTTP 500) when saving page with accented character in title, on Windows/IIS
: IIS expects URLs to be encoded using legacy single-byte encodings, but MediaWiki uses UTF-8. Follow these instructions to resolve this: https://support.microsoft.com/en-us/help/2277918/fix-a-php-application-that-depends-on-the-request-uri-server-variable ({{T|269673}})

; Error contacting the Parsoid/RESTBase server (HTTP 500) when trying to edit an existing page with VisualEditor
: Persisting in MW 1.35.x . See {{T|270377}}

; Error loading data from server<nowiki>:</nowiki> HTTP 500. Would you like to retry?
: Possible reasons for this problem:
:* On new installs, "curl", "php5-curl", or "php7.0-curl" (or other package appropriate to your PHP version) is not installed on the server.
:* setMwApi uri is set incorrectly with e.g. https instead of http.
:* Bad rewrite rules in the apache configuration that would cause API failures.
:* The SSL/TLS certificates are expired.
:* When the directory set in {{wg|TmpDirectory}} (for example "/tmp") has not write permissions.
:* When running Windows Authentication with Apache, you would need to white-list 127.0.0.1 in your Apache conf, as Apache doesn't have read access. <syntaxhighlight copy lang="apache">
<Directory "D:/Wiki/htdocs">
    ...

    Allow from 127.0.0.1
    Satisfy Any
</Directory>
</syntaxhighlight>

; No visible error (Appears to load forever)
: Check the parsoid log file, and consult {{ll|Parsoid/Troubleshooting}}.

; parsoidserver-http-bad-status<nowiki>:</nowiki> 401
: Caused by read or edit restrictions (aka 'private wiki'). If you've set up a private wiki and don't want to use cookie forwarding, you can [[User:Andru~mediawikiwiki/Allow Parsoid Server|explicitly remove restrictions for Parsoid by IP address]]. (See [[Extension talk:VisualEditor/2020#h-Maybe_they'll_fix_it-2020-10-02T19:05:00.000Z]] and the ticket: [[phab:T268277|MW 1.35.0 "Error contacting the Parsoid/RESTBase server: http-bad-status" on a private wiki]])

; parsoidserver-http-curl-error<nowiki>:</nowiki> couldn't connect to host.
: Parsoid is not running, or {{phpi|$wgVirtualRestConfig['modules']['parsoid']['url']}} is not set correctly.

; parsoidserver-http-curl-error<nowiki>:</nowiki> Failed to connect to ....<nowiki>:</nowiki> Permission denied.
: Can be caused by a cURL request on a [[:en:Security-Enhanced Linux|Security-Enhanced Linux]] (SELinux, like CentOS) to a non standard port like 8000 in the example configuration above, see https://www.akashif.co.uk/php/curl-error-7-failed-to-connect-to-permission-denied and https://www.centos.org/forums/viewtopic.php?f=47&t=53223&p=225372#p225372

; parsoidserver-http-not-acceptable<nowiki>:</nowiki> 406
: Caused by Parsoid 0.9 enforcing clients to return a 1.6.0 and greater HTML version string in the header. This most likely affects Debian users as they are using slightly older MediaWiki versions with MediaWiki's Parsoid APT repository. This can be fixed by either downgrading to 0.8 (not easy as 0.8 no longer exists in the repository) or by editing <code>/usr/lib/parsoid/src/lib/config/ParsoidConfig.js</code> so that <syntaxhighlight lang="javascript" inline>ParsoidConfig.prototype.strictAcceptCheck = false;</syntaxhighlight>. The latter will be overwritten on any package upgrade, so it is up to the administrator to lock the package and keep on top of updates manually.

; parsoidserver-http-not-found<nowiki>:</nowiki> 404 (or timeout)
: Caused by wrong path to MediaWiki API endpoint. Set correct url to the right path to <code>api.php</code> in Parsoid's <code>localsettings.js</code> config file. If you have set up following the recommendations, your API path would be "http://localhost/w/api.php". Add this API path to "localsettings.js" like "{{phpi|parsoidConfig.setMwApi({uri: 'http://localhost/w/api.php' });}}".

; Synology
: Make sure you click the options that engage VisualEditor. If the VE returns an error when you try to save the edited page, this likely means you did not enable zlib (an optional dependency, but required for VE) during installation.
:* Go to: MainMenu (the four little boxes in the left corner of the Synology screen) and choose Web Station
:* In the left sidebar choose <nowiki></></nowiki> Script Language Settings
:* Choose MediaWiki and click Edit and then Extensions
:* At the very bottom of the list, click the zlib box. You will also want to enable the optional dependencies mysql, imagick and zip.

== Development documentation ==
* {{ll|VisualEditor/Gadgets}} - non formal guide for hacking VisualEditor. Includes code snippets and other information useful to gadget authors (and other custom JS devs).
* [https://doc.wikimedia.org/VisualEditor/master/js/ API Documentation] - information on some VisualEditor JS classes.

== See also ==
* {{ll|Extension:Slash Commands|Slash Commands}} – Adds "slash commands", i.e., text shortcuts that start with a slash ("/") and trigger specific actions via the visual editor. This is an alternative to the equivalent backslash ("\") tool built into the editor.
* {{ll|Extension:VisualEditorPlus|VisualEditorPlus}} – Extends the shortcut options of the visual editor.
* {{ll|Extension:VEForAll|VEForAll}} - enabling visual editor in forms extensions

{{OnWikimedia}}
{{Used by}}

{{Feedback
| thing = VisualEditor
| author = {{ll|Editing}} team
| irc = mediawiki-visualeditor
| ml = 
| ml2 = 
| phab = visualeditor
}}

[[Category:WYSIWYG extensions{{#translation:}}]]
[[Category:VisualEditor{{#translation:}}]]