optional_permissions

"optional_permissions": [
  "*://developer.mozilla.org/*",
  "webRequest"
]

Use the optional_permissions key to list permissions which you want to ask for at runtime, after your extension has been installed.

While the permissions key lists permissions which your extension needs if it is to be installed at all, optional_permissions lists permissions which your extension doesn't need at install time, but which it might need to ask for at runtime at some point after it has been installed. To ask for a permission, use the permissions API. Asking for a permission will probably present the user with a dialog asking them to grant the permission to your extension.

The key can contain two kinds of permissions:

• host permissions: these are the same as the host permissions you can specify in the permissions key.
• API permissions. You can include any of the following here, but not in all browsers: check the compatibility table for browser-specific details:
  • activeTab
  • background
  • bookmarks
  • clipboardRead
  • clipboardWrite
  • contentSettings
  • contextMenus
  • cookies
  • debugger
  • geolocation
  • history
  • idle
  • management
  • notifications
  • pageCapture
  • tabs
  • topSites
  • webNavigation
  • webRequest
  • webRequestBlocking

Note that this is a subset of the API permissions allowed in permissions.

Of this set, the following permissions are granted silently, without a user prompt: activeTab, cookies, idle, webRequest, webRequestBlocking.

Example

 "optional_permissions": ["*://developer.mozilla.org/*"]

Enable the extension to ask for privileged access to pages under developer.mozilla.org.

  "optional_permissions": ["tabs"]

Enable the extension to ask for access to the privileged pieces of the tabs API.

  "optional_permissions": ["*://developer.mozilla.org/*", "tabs"]

Enable the extension to ask for both of the above permissions.

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.