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  7. BrowserSetting
  8. set()

set()

In This Article
  1. Syntax
    1. Parameters
    2. Return value
  2. Browser compatibility
  3. Example

Use BrowserSetting.set() to change the browser setting to a new value.

There are some rules that can restrict when extensions are able to change settings:

  • some settings are locked, so they can't be changed by extensions at all
  • if multiple extensions try to modify the same setting, then extensions are given a precedence ordering based on when they were installed. More-recently installed extensions have precedence over less-recently installed extension.

This means that if extension X tries to change a setting:

  1. If the setting is locked, then the setting is not changed. However, X's change is remembered, and it is stored in a queue, ordered by X's precedence relative to any other extensions that tried to change the setting. If the setting becomes unlocked later on, the first extension in the queue gets to change the setting.
  2. Otherwise, if no other extension has already changed the setting, then X succeeds in changing the setting, and is then said to "control" the setting.
  3. Otherwise, if a lower-precedence extension Y has already changed the setting, then X succeeds in changing the setting, and now controls the setting. However, Y's change is remembered, and is stored in a queue in precedence order. If X subsequently clears its value, or if X is disabled or uninstalled,  the first extension in the queue gets to make its change to the setting.
  4. Otherwise, if a higher-precedence extension Z has already changed the setting, then X does not succeed in changing the setting, but its change is queued. If Z subsequently clears its value, or if Z is disabled or uninstalled, the first extension in the queue gets to make its change to the setting.

An extension can find out which of these scenarios applies by examining the "levelOfControl" property returned from a call to BrowserSetting.get().

The BrowserSetting.set() method returns a Promise that resolves to a boolean: if an attempt to change a setting actually results in the setting being changed (scenarios 2 and 3 above) the boolean is true: otherwise it is false.

Syntax

var setting = setting.set(
  details     // object
)

Parameters

details
An object that must contain the following property:
value
any. The value you want to change the setting to. Its type depends on the particular setting.

Return value

A Promise that will be fulfilled with a boolean: true if the setting was modified, false otherwise (for example, because the extension did not control the setting).

Browser compatibility

See types.BrowserSetting.

Example

Modify the hyperlinkAuditingEnabled setting:

function onSet(result) {
  if (result) {
    console.log("Value was updated");
  } else {
    console.log("Value was not updated");
  }
}
browser.browserAction.onClicked.addListener(() => {
    var setting = browser.privacy.websites.hyperlinkAuditingEnabled.set({
      value: false
    });
    setting.then(onSet);
});

Acknowledgements

This API is based on Chromium's chrome.types API.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

// Copyright 2015 The Chromium Authors. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//    * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//    * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Document Tags and Contributors

Tags: 
  • Add-ons
  • API
  • BrowserSetting
  • Extensions
  • Privacy
  • Reference
  • set
  • WebExtensions
 Contributors to this page: andrewtruongmoz, wbamberg, jwhitlock
 Last updated by: andrewtruongmoz, Jul 17, 2017, 1:23:17 PM
See also
  1. Browser extensions
  2. Getting started
    1. What are extensions?
    2. Your first extension
    3. Your second extension
    4. Anatomy of an extension
    5. Example extensions
  3. How to
    1. Intercept HTTP requests
    2. Modify a web page
    3. Add a button to the toolbar
    4. Implement a settings page
  4. User interface
    1. Introduction
    2. Toolbar button
    3. Address bar button
    4. Sidebar
    5. Context menu items
    6. Options page
    7. Bundled web pages
    8. Notifications
    9. Address bar suggestions
    10. Developer tools panels
  5. Concepts
    1. Using the JavaScript APIs
    2. Content scripts
    3. Match patterns
    4. Internationalization
    5. Content Security Policy
    6. Native messaging
  6. Porting
    1. Porting a Google Chrome extension
    2. Porting a legacy Firefox extension
    3. Embedded WebExtensions
    4. Comparison with the Add-on SDK
    5. Comparison with XUL/XPCOM extensions
    6. Chrome incompatibilities
    7. Differences between desktop and Android
  7. Firefox workflow
    1. Temporary Installation in Firefox
    2. Debugging
    3. Developing for Firefox for Android
    4. Getting started with web-ext
    5. web-ext command reference
    6. Extensions and the Add-on ID
    7. Publishing your extension
  8. JavaScript APIs
    1. Browser support for JavaScript APIs
    2. alarms
    3. bookmarks
    4. browserAction
    5. browsingData
    6. commands
    7. contextMenus
    8. contextualIdentities
    9. cookies
    10. devtools.inspectedWindow
    11. devtools.network
    12. devtools.panels
    13. downloads
    14. events
    15. extension
    16. extensionTypes
    17. history
    18. i18n
    19. identity
    20. idle
    21. management
    22. notifications
    23. omnibox
    24. pageAction
    25. permissions
    26. privacy
    27. proxy
    28. runtime
    29. sessions
    30. sidebarAction
    31. storage
    32. tabs
    33. topSites
    34. types
      1. Types
        1. BrowserSetting
    35. webNavigation
    36. webRequest
    37. windows
  9. Manifest keys
    1. applications
    2. author
    3. background
    4. browser_action
    5. chrome_settings_overrides
    6. chrome_url_overrides
    7. commands
    8. content_scripts
    9. content_security_policy
    10. default_locale
    11. description
    12. developer
    13. devtools_page
    14. homepage_url
    15. icons
    16. incognito
    17. manifest_version
    18. name
    19. omnibox
    20. optional_permissions
    21. options_ui
    22. page_action
    23. permissions
    24. protocol_handlers
    25. short_name
    26. sidebar_action
    27. version
    28. web_accessible_resources
  10. Themes
  11. Publishing add-ons
  12. Guides
    1. Signing and distribution overview
    2. Submit an add-on
    3. Creating an appealing listing
    4. Review policies
    5. Developer agreement
    6. Featured add-ons
    7. Contact addons.mozilla.org
  13. Community and support
  14. Channels
    1. Add-ons blog
    2. Add-on forums
    3. Stack Overflow
    4. Development newsgroup
    5. IRC Channel
  15. Legacy add-ons
  16. Legacy technologies
    1. Add-on SDK
    2. Legacy Firefox for Android
    3. Bootstrapped extensions
    4. Overlay extensions