Security News > 2020 > January > Facebook knows a lot about your online habits – here’s how to stop it
Those third parties send Facebook information about your activities including things like opening an app on your mobile, logging into it online using your Facebook ID, or even just visiting a site.
This piece of Facebook code is known more generically as a web bug, and it logs your activities on any site that embeds it, sending that information back to Facebook.
Facebook also knows what device you use, and it has your personal information too, so it can index your activity on all these sites against your real identity, not just a number.
Hit 'Turn Off', and within two days Facebook will stop connecting events from that third-party site or app with your account.
What can you do if you want to continue using the social network but its Off-Facebook Activity functionality isn't enough for you? Firefox offers a Facebook Container that creates a boundary between Facebook sites and the rest of the web.