A new extension, called Facebook Disconnect, blocks contact between your
browser and Facebook's servers when you're browsing the regular Web. Facebook Disconnect will prevent the sending of data back to Facebook
across the one million sites that use the Facebook Connect service.
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While there are other ways to do this manually, they usually amount to a full block on *.facebook.com/* traffic, whereas this extension still allows normal use of your Facebook account and leaves "like" buttons on websites completely intact for you to continue sharing.