For safeguarding internet privacy
Privacy Badger is a browser extension that blocks or limits the tracking technologies that marketers use to view your search history for products you’ve shown interest in, which allows them to advertise those products on sites such as Facebook and Twitter. The free extension works with Chrome, Firefox, and Opera.
Facebook Container prevents Facebook from following your movements around other websites. The extension only works with Firefox, and it might disable Facebook peripherals that you might like, such as having your profile embedded in comment sections on other websites. That’s a small price to pay, though, for the privacy protection.