The Firefox desktop browser now enables Total Cookie Protection by default. This feature, which initially launched in 2021 to enhance the security of Private Browsing mode, limits the third-party cookies’ ability to track you throughout the web.

A cookie is a small file that lets a site identify you and “remember” your activities. They’re useful to the end-user and provide important information to a website’s owner. If you delete all browser cookies, for example, you will log out of all websites (and reset preferences on websites that don’t rely on user accounts).

Unfortunately, cookies are basically just trackers. And if a company like Facebook decides to stick its cookies on other peoples’ websites, it can quickly build an advertising profile based on your web history, interests, accounts, and location. Unless you love creepy targeted ads, third-party cookies aren’t useful to you and are arguably a violation of your privacy.

Firefox’s Total Cookie Protection doesn’t kill cookies; it simply reduces third-party cookies’ ability to track your activity or phone home to their owners. Mozilla calls this a “cookie jar” system—each website has its own “jar” where cookies operate correctly, but one site can’t stick its hands in another site’s “cookie jar.”

This approach strikes the balance between eliminating the worst privacy properties of third-party cookies — in particular the ability to track you — and allowing those cookies to fulfill their less invasive use cases (e.g. to provide accurate analytics). With Total Cookie Protection in Firefox, people can enjoy better privacy and have the great browsing experience they’ve come to expect.

Other browsers, particularly Microsoft Edge, offer similar cookie protection. Though as we learned in the recent DuckDuckGo scandal, you probably shouldn’t take a company’s privacy claims at face value. Tools like Total Cookie Protection are incredible, but they shouldn’t be your last line of defense if you’re deeply concerned about privacy. (For what it’s worth, Mozilla has a solid track record for user privacy and doesn’t oversell Total Cookie Protection’s capabilities.)

I should mention that Total Cookie Protection is also available in Firefox Focus (iOS/Android), a privacy-minded mobile browser that blocks trackers and doesn’t save any web history or logins.

Source: Mozilla