SmartBlock feature lands with Firefox 87

Mozilla has announced the launch of its latest version of the popular Firefox browser. The new version is Firefox 87, and with its launch comes a new feature called SmartBlock aimed at improving privacy while browsing. SmartBlock is described as an intelligent tracker blocking mechanisms for Firefox Private Browsing and Strict Mode.

SmartBlock is designed to ensure strong privacy protections and that Firefox provides "a great web browsing experience." Mozilla says it believes privacy is a fundamental right and that everyone deserves to have their privacy protected while they surf the web. Firefox has had features in place since 2015 to provide strong privacy, including the integrated Content Blocking feature that operates in Private Browsing and Strict Tracking Protection modes.

That feature automatically blocks third-party scripts, images, and other content from being loaded from cross-site tracking companies reported by Disconnect. The blocking of those scripts and other content prevents those companies from tracking users while surfing the web. The challenge with blocking trackers outright is that Firefox risks blocking components that are required for some websites to function properly.

The result is webpages that load with images that don't appear, features not working, poor performance, or the page may not load all. This is where SmartBlock comes in by intelligently fixing webpages that are broken by tracking protections without compromising user privacy. SmartBlock can do that by providing local stand-ins from blocked third-party tracking scripts. Firefox says its stand-in scripts behave "just enough" the original tracking scripts that the website works properly.

Those scripts allow broken sites relying on the original scripts to load with functionality intact. SmartBlock scripts are bundled with Firefox, and no third-party content from the trackers is loaded at all. Mozilla is clear that there is no chance for the third-party content to track users and that the stand-in scripts Firefox loads don't contain any code that supports tracking.