The Mozilla Foundation released today a Firefox add-on that isolates the Facebook website and all its domains to a separate "container," effectively stopping Facebook from tracking users across other websites on the Web.
That experimental feature allowed users access to four different "containers" (identities, browser sessions) that worked on top of four separate browser database that each stored a different set of cookies, browsing cache, indexedDB, and localStorage data.
The Container experiment was a success, but Mozilla decided to make the feature available as an add-on named "Firefox Multi-Account Containers," instead of incorporating it into Firefox.
The new Facebook Container add-on is built on this older experiment/extension. The "Facebook Container" automatically activates whenever the user opens the facebook.com website.
At first use, the add-on will delete any existing Facebook cookies and prompt users to log back into their Facebook accounts. The add-on will then create a separate database that will keep all Facebook-related data, such as cookies, cache data, and more.
The add-on will use this data only when browsing the main Facebook site and will show a blue indicator in the address bar when the Facebook container becomes active.
When users will visit other websites, users will be utilizing the browser's normal database.
The add-on will also block any Facebook domains from loading, effectively stopping Facebook from tracking people as they move across the web, a capability that Facebook has thanks to its social widgets and buttons embedded on countless of sites.
"This prevents Facebook from associating information about your activity on websites outside of Facebook to your Facebook identity," the Mozilla team says.
Users will still be able to use those social sharing buttons when they press them, but features like logging into other websites using Facebook credentials may be broken.
Mozilla released this add-on after the revelations in the Cambridge Analytica scandal. The Foundation also suspended its Facebook advertising program as a way to protest Facebook's privacy intrusive practices.