sync storage area. Items in
sync storage are synced by the browser, and are available across all instances of that browser that the user is logged into (e.g. via Firefox sync, or a Google account), across different devices.
For Firefox a user must have
Add-ons checked under the "Sync Settings" options in "about:preferences".
Note that the implementation of
storage.sync in Firefox relies on the Add-on ID. If you use
storage.sync, you must set an ID for your extension using the
applications manifest.json key.
The main use case of this API is to store preferences about your extension and allow the user to sync them to different profiles. You can store up to 100KB of data using this API. If you try to store more than this, the call will fail with an error message. The API is provided without any guarantees about uptime or performance.
sync object implements the methods defined on the
- Retrieves one or more items from the storage area.
- Gets the amount of storage space (in bytes) used one or more items being stored in the storage area.
- Stores one or more items in the storage area. If the item already exists, its value will be updated.
- Removes one or more items from the storage area.
- Removes all items from the storage area.
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.
|Chrome||Edge||Firefox||Firefox for Android||Opera|
Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.
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