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chrome_settings_overrides

Type Object
Mandatory No
Example
  "chrome_settings_overrides" : {
    "homepage": "https://developer.mozilla.org/"
  }
  "chrome_settings_overrides": {
    "search_provider": {
      "name": "Discogs",
      "search_url": "https://www.discogs.com/search/?q={searchTerms}",
      "keyword": "disc",
      "favicon_url": "https://www.discogs.com/favicon.ico"
    }
  }

Use the chrome_settings_overrides key to override certain browser settings. Two settings are available:

  • "homepage", which enables you to override the browser's home page
  • "search_provider", which enables you to add a new search engine.

Syntax

The chrome_settings_overrides key is an object that may have the following properties:

Name Type Description
homepage String

Defines the page to be used as the browser's homepage.

The replacement is given as a URL. The URL may:

  • point to a file bundled with the add-on, in which case it is given as a URL relative to the manifest.json file
  • be a remote URL, such as "https://developer.mozilla.org/".

If two or more add-ons both set this value, then the last one that gets to run (i.e. the most recently installed or enabled) one wins. If the user changes the homepage using the browser's preferences UI, then this will override the add-on's choice.

To override new tabs, use "chrome_url_overrides" instead.

This is a localizable property.

search_provider Object

Defines a search provider to add to the browser.

The search provider has a name and a primary search URL. Alternative URLs may be provided, including URLs for more specialized searches like image search. In the URL you supply, use "{searchTerms}" to interpolate the search term into the URL, like: https://www.discogs.com/search/?q={searchTerms}. You can also provide POST parameters to be sent along with the search.

The search provider will be presented to the user alongside the built-in providers. If you include the is_default property and set it to true, the new search provider will be the default option. By supplying the keyword property, you enable the user to select your search provider by typing the keyword into the search/address bar before the search term.

This is an object with the properties listed below. All string properties are localizable.

name
String. The search engine's name, displayed to the user.
search_url
String. URL used by the search engine. This must be an HTTPS URL.
is_default
Boolean: True if the search engine should be the default choice.
alternate_urls Optional
Array of String. An array of alternative URLs that can be used instead of search_url.
encoding Optional
String. Encoding of the search term, specified as a standard character encoding name, such as "UTF-8".
favicon_url Optional
String: URL pointing to an icon for the search engine. This must be a absolute HTTP or HTTPS URL.
image_url Optional
String: URL used for image search.
image_url_post_params Optional
String: POST parameters to send to image_url.
instant_url Optional
String: URL used for instant search.
instant_url_post_params Optional
String: POST parameters to send to instant_url.
keyword Optional
String. Address bar keyword for the search engine.
prepopulated_id Optional
The ID of a built-in search engine to use.
search_url_post_params Optional
String: POST parameters to send to search_url.
suggest_url Optional
String: URL used for search suggestions.
suggest_url_post_params Optional
String: POST parameters to send to suggest_url.

Example

"chrome_settings_overrides": {
  "homepage": "https://developer.mozilla.org/"
}
"chrome_settings_overrides": {
    "search_provider": {
      "name": "Discogs",
      "search_url": "https://www.discogs.com/search/?q={searchTerms}",
      "keyword": "disc",
      "favicon_url": "https://www.discogs.com/favicon.ico"
    }
  }

Browser compatibility

ChromeEdgeFirefoxFirefox for AndroidOpera
Basic supportYesNo5555Yes
search_providerYesNoNoNoYes
startup_pagesYesNoNoNoYes

Document Tags and Contributors

 Contributors to this page: wbamberg, delete12345
 Last updated by: wbamberg,