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Add-ons
  1. MDN
  2. Mozilla
  3. Add-ons
  4. Themes
  5. Lightweight themes
  6. Frequently Asked Questions for Lightweight themes

Frequently Asked Questions for Lightweight themes

In This Article
  1. Introducing Lightweight themes
    1. What are Lightweight themes?
    2. What kind of computers and operating systems do Lightweight themes work with?
    3. What's the difference between Lightweight themes and Complete Themes?
  2. Installing Lightweight themes
    1. How do I add Lightweight themes to my Firefox?
    2. Are Lightweight themes free?
  3. Using Lightweight themes
    1. How do I change my current Lightweight theme?
    2. If I have a Complete Theme installed, will Lightweight themes still work?
    3. How do I undo a Lightweight theme?
    4. How do I provide feedback?
  4. Creating Your Own Themes
    1. Can I create my own Theme?
    2. Are there any content guidelines?
    3. Do I still retain ownership over artwork that I upload?
    4. After creating a Lightweight theme, can I edit the design?
    5. What's the maximum file size allowable for my Lightweight theme?

Introducing Lightweight themes

What are Lightweight themes?

Lightweight themes are easy-to-install, easy-to-use skins that change the look of your Firefox web browser. There are hundreds of thousands community-designed themes to choose from, with more added every day. Start looking here for designs that fit your style.

What kind of computers and operating systems do Lightweight themes work with?

Lightweight themes work with any type of computer that has Firefox installed. This includes Mac, Linux, Windows, and Android platforms.

What's the difference between Lightweight themes and Complete Themes?

Complete Themes transform the look of your browser with styles for the window frame, address bar, buttons, tabs, and menus.

Lightweight themes change just the header and footer areas of your browser. You can instantly preview a design and install it in one click without needing to restart.

Installing Lightweight themes

How do I add Lightweight themes to my Firefox?

In just a few seconds, you can install a theme and transform the look of your Firefox web browser. Preview any theme by simply mousing over it; the design appears in your browser header so you can "try it on." When you're ready, just click the green Add to Firefox button. Once a theme is installed, it is saved in the Add-ons Manager, where you can enable or disable them as you wish. Simply go to the Tools > Add-ons menu and click on the Appearance tab.

Are Lightweight themes free?

Yes. Themes are free to download and free to use.

Using Lightweight themes

How do I change my current Lightweight theme?

There are two easy ways to change your theme. You can either:

  • Visit the gallery, choose your favorite theme, and click on your choice to instantly change the look of your browser.
  • Once a theme is installed, it is saved in the Add-ons Manager, where you can enable or disable them as you wish. Simply go to the Tools > Add-ons menu and click on the Appearance tab.

If I have a Complete Theme installed, will Lightweight themes still work?

Yes. If you have a non-default Complete Theme installed, Firefox will automatically switch to a default theme in order to allow you to use your choice of Lightweight theme designs.

How do I undo a Lightweight theme?

To undo the design you most recently selected, go to Tools > Add-ons in the menu bar and select the Appearance tab. Next to the theme you want to undo, click the Disable button.

How do I provide feedback?

We're always looking for ways to improve themes, and would love to hear what you think. Visit the themes forum to send us your feedback.

Creating Your Own Themes

Can I create my own Theme?

Absolutely! All you need to do is create two graphics files in your favorite graphics editing program (e.g., Photoshop). To get started read more about how to create a theme.

Are there any content guidelines?

Yes. We are big fans of creativity, but want to ensure that the art displayed in the Themes gallery meets a basic set of guidelines. Please review the Terms of Service and Conditions of Use for authoritative and complete language.

Do I still retain ownership over artwork that I upload?

Yes. Your artwork will always be your artwork.

After creating a Lightweight theme, can I edit the design?

Yes. If at any point you need to edit or delete your theme design after it has been submitted to the gallery, you can access it from the Submissions dashboard. From there, you can view your current designs. By clicking on each, you can make changes to each design's settings.

What's the maximum file size allowable for my Lightweight theme?

The theme you upload may not exceed 300 KB for the header or the footer image.

Couldn't find the answer you're looking for? Consider visiting the Firefox support website or the Themes forum for more help.

Document Tags and Contributors

 Contributors to this page: andrewtruongmoz, caitmuenster, wbamberg, FraterTenc, atsay, jswisher, psx1337, kmaglione
 Last updated by: andrewtruongmoz, Jun 8, 2017, 11:25:58 AM
See also
  1. WebExtensions
  2. Getting started
    1. What are WebExtensions?
    2. Your first WebExtension
    3. Your second WebExtension
    4. Anatomy of a WebExtension
    5. Example WebExtensions
  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 add-on
    3. Embedded WebExtensions
    4. Comparison with the Add-on SDK
    5. Comparison with XUL/XPCOM extensions
    6. Chrome incompatibilities
  7. Firefox workflow
    1. Temporary Installation in Firefox
    2. Debugging
    3. Getting started with web-ext
    4. web-ext command reference
    5. WebExtensions and the Add-on ID
    6. Publishing your WebExtension
  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
    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. Add-on SDK
  11. Getting started
    1. Installation
    2. Getting started
    3. Troubleshooting
  12. High-Level APIs
    1. addon-page
    2. base64
    3. clipboard
    4. context-menu
    5. hotkeys
    6. indexed-db
    7. l10n
    8. notifications
    9. page-mod
    10. page-worker
    11. panel
    12. passwords
    13. private-browsing
    14. querystring
    15. request
    16. selection
    17. self
    18. simple-prefs
    19. simple-storage
    20. system
    21. tabs
    22. timers
    23. ui
    24. url
    25. webextension
    26. widget
    27. windows
  13. Low-Level APIs
    1. /loader
    2. chrome
    3. console/plain-text
    4. console/traceback
    5. content/content
    6. content/loader
    7. content/mod
    8. content/symbiont
    9. content/worker
    10. core/heritage
    11. core/namespace
    12. core/promise
    13. dev/panel
    14. event/core
    15. event/target
    16. frame/hidden-frame
    17. frame/utils
    18. fs/path
    19. io/byte-streams
    20. io/file
    21. io/text-streams
    22. lang/functional
    23. lang/type
    24. loader/cuddlefish
    25. loader/sandbox
    26. net/url
    27. net/xhr
    28. places/bookmarks
    29. places/favicon
    30. places/history
    31. platform/xpcom
    32. preferences/event-target
    33. preferences/service
    34. remote/child
    35. remote/parent
    36. stylesheet/style
    37. stylesheet/utils
    38. system/child_process
    39. system/environment
    40. system/events
    41. system/runtime
    42. system/unload
    43. system/xul-app
    44. tabs/utils
    45. test/assert
    46. test/harness
    47. test/httpd
    48. test/runner
    49. test/utils
    50. ui/button/action
    51. ui/button/toggle
    52. ui/frame
    53. ui/id
    54. ui/sidebar
    55. ui/toolbar
    56. util/array
    57. util/collection
    58. util/deprecate
    59. util/list
    60. util/match-pattern
    61. util/object
    62. util/uuid
    63. window/utils
  14. Firefox for Android
  15. Getting started
    1. Walkthrough
    2. Debugging
    3. Code snippets
  16. APIs
    1. Accounts.jsm
    2. BrowserApp
    3. HelperApps.jsm
    4. Home.jsm
    5. HomeProvider.jsm
    6. NativeWindow
    7. Notifications.jsm
    8. PageActions.jsm
    9. Prompt.jsm
    10. RuntimePermissions.jsm
    11. Snackbars.jsm
    12. Sound.jsm
    13. Tab
  17. Legacy
  18. Restartless extensions
    1. Overview
  19. Overlay extensions
    1. Overview
  20. Themes
  21. Lightweight themes
    1. Overview
  22. Complete themes
    1. Overview
  23. Publishing add-ons
  24. Guides
    1. Signing and distribution overview
    2. Submit an add-on
    3. Review policies
    4. Developer agreement
    5. Featured add-ons
    6. Contact addons.mozilla.org
  25. Community and support
  26. Channels
    1. Add-ons blog
    2. Add-on forums
    3. Stack Overflow
    4. Development newsgroup
    5. IRC Channel