Firefox's new SmartBlock makes private browsing less of a headache

Firefox's new SmartBlock tool ensures websites work correctly when you're trying to avoid being tracked by marketers.

Credit: Brad Chacos/IDG

Firefox 87 just dropped with a killer new feature for privacy buffs: SmartBlock for private browsing.

Mozilla’s browser has been pushing hard on pro-privacy features recently in a bid to differentiate itself from Google’s juggernaut Chrome. Along those lines, Firefox offers a Tracking Protection tool for its Private Browsing and Strict Traction Protection Modes that “automatically blocks third-party scripts, images, and other content from being loaded.” Blocking those scripts prevents users from being tracked across sites—but it can sometimes result in websites rendering slowly or incorrectly.

SmartBlock aims to fix that. Mozilla’s Thomas Wisniewski explains how:

“SmartBlock [provides] local stand-ins for blocked third-party tracking scripts. These stand-in scripts behave just enough like the original ones to make sure that the website works properly. They allow broken sites relying on the original scripts to load with their functionality intact.

The SmartBlock stand-ins are bundled with Firefox: no actual third-party content from the trackers are loaded at all, so there is no chance for them to track you this way. And, of course, the stand-ins themselves do not contain any code that would support tracking functionality.”

firefox 87 Brad Chacos/IDG

Up to date with Firefox 87!

We haven’t had a chance to give SmartBlock a test drive yet, but it sure sounds good on paper. If you want to start using the new feature now, you can update your existing Firefox installation to version 87 by opening the browser’s options menu and heading to Help > About Firefox.

While you’re mucking around in the options menu, also check out the Protections Dashboard option for a personalized rundown of the privacy protections Firefox made for you while you’ve been browsing.

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Brad Chacos

Brad Chacos

PC World (US online)
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