You have probably been reading recently about the way that millions of users’ information on Facebook was harvested for marketing and political purposes. A subsequent story has also revealed that Facebook stores details of all the people you contact and phone via its Messenger service.

Let’s be clear here. Facebook is a data company. They make money selling adverts, and the more accurately they can target those adverts then the more money they make from advertisers. If you “like” a page on Facebook that’s about cars, and lots of your friends “like” those pages too, and if you use Facebook Messenger to contact people who “like” cars, then you’re going to see a lot of adverts for cars. That’s the way that Facebook works.

If you’re worried about how Facebook uses your data, and you use Firefox, then check out a brand new extension called Facebook Container. While it doesn’t prevent Facebook from getting to know more about you, it does prevent Facebook from being able to access data and cookies from other sites. Normally, web sites get to share data about their users because each web site uses the same advertising network, and so the controls that normally prevent one site from seeing another site’s cookies don’t apply. But Facebook Container helps to block that. So your likes and preferences on other web sites won’t find their way into Facebook’s databases, and vice versa.

You can read more about this extension, and download it, at https://blog.mozilla.org/firefox/facebook-container-extension/ .

It’s free.