We do not recommend flipping this preference to true as doing so may result in data loss. If you notice any regressions, please check your about:config preferences to ensure that is set to false and then file a bug. We encourage you to use the Firefox Beta channel to test all extension features that use the storage.sync API to see how they behave if the client-side storage quota is exceeded before Firefox 79 is released. However, the extension should still successfully retrieve existing data. If your extension tries to store data above quota limits, the storage.sync API call will raise an error.However, attempting to add new data will fail. If your extension previously stored data above quota limits, all that data will be migrated and available to your extension, and will be synced.You can make a call using to estimate how much data your extension is storing locally over the limit.If you are the developer of an extension that syncs extension storage, you should be aware that the new implementation now enforces client-side quota limits. After the migration, the data will be stored locally in a new storage-sync2.sqlite file in the profile directory. The storage.sync area has been ported to a new Rust-based implementation, allowing extension storage to share the same infrastructure and backend used by Firefox Sync.Įxtension data that had been stored locally in existing profiles will automatically migrate the first time an installed extension tries to access storage.sync data in Firefox 79. Items that extensions store in this area are automatically synced to all devices signed in to the same Firefox Account, similar to how Firefox Sync handles bookmarks and passwords.

Firefox 79, which will be released on July 28, includes changes to the storage.sync area.

Firefox local storage