Third-party trackers - Waterfox Support

Third-party trackers are invisible snippets of code that are present on many websites. They collect and send information about your browsing history to other companies, often for advertising purposes. If the same third-party tracker is present on multiple sites, it can build a more complete profile about you over time. When you feel like an advertisement is following you around while you browse, this is a result of third-party trackers.