Don't like Facebook secretly tracking your online purchases and telling your friends what you bought? Users of the Firefox we browser can use an easy add-on that jams the beacon's signal. Just install the BlockSite add-on, and then add http://*facebook.com/beacon/* as one of the blocked sites. Make sure to keep those asterisks in. If that sounds a little complicated, this step-by-step walk-through at Wikihow shows you how it's done. Alternatively, you could also add the same url to AdBlockPlus, another Firefox extension.

How to Block Facebook Beacon [WikiHow]
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