Firefox will look at your history to show Suggested Tile ads
Starting next week, Firefox beta users will start seeing "Suggested" tiles whenever they open a new tab. These are ad tiles clearly marked as such (see bottom left above), which are a separate entity from the Directory tiles Mozilla launched in 2014. See …
Coming soon to Firefox: More ads!
Firefox's Suggested Tiles Ads Will Be Based On Browsing History
Firefox Will Soon Get Sponsored Suggested Tiles Based On Your Browsing History