Enables WebExtensions to store and retrieve data, and listen for changes to stored items.
The storage system is based on the Web Storage API, with a few differences.
Although this API is similar to
Window.localStorage it is recommended that you don't use
Window.localStorage in add-on code. Firefox will clear data stored by add-ons using the localStorage API in various scenarios where users clear their browsing history and data for privacy reasons, while data saved using the
storage.local API will be correctly persisted in these scenarios.
- An object representing a storage area.
- An object representing a change to a storage area.
storage has three properties, which represent the different types of available storage area.
- Represents the
syncstorage area. Items in
syncstorage are synced by the browser, and are available across all instances of that browser that the user is logged into, across different devices.
- Represents the
localstorage area. Items in
localstorage are local to the machine the extension was installed on.
- Represents the
managedstorage area. Items in
managedstorage are set by the domain administrator and are read-only for the extension. Trying to modify this namespace results in an error.
- Fired when one or more items change in a storage area.
|Chrome||Edge||Firefox||Firefox for Android||Opera|
The "Chrome incompatibilities" section is included from https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Chrome_incompatibilities using the WebExtChromeCompat macro.
If you need to update this content, edit https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Chrome_incompatibilities, then shift-refresh this page to see your changes.
Promises are not supported in Edge. Use callbacks instead.
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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