Firefox 42 Blocks Tracking Ads, Enhances Private Browsing

9 Ways To Bulletproof Your Privacy Policy

Mozilla rolled out its latest version of the Firefox browser (v42) on Nov. 3 with a new feature that actively blocks anything that tracks you online, including ads and social share buttons. Firefox 42 also includes patches for some security vulnerabilities.

The new feature called Tracking Protection is only enabled when the user is in Private Browsing mode. It continues Firefox's focus on privacy.

"With the release of Tracking Protection in Firefox Private Browsing we are leading the industry by giving you control over the data that third parties receive from you online. No other browser's Private Browsing mode protects you the way Firefox does -- not Chrome, not Safari, not Microsoft Edge or Internet Explorer," vice president of the Firefox product Nick Nguyen wrote on the Firefox blog. 

Nguyen went on in his statement to explain in further detail what the process will do for users.

"Private Browsing with Tracking Protection in Firefox for Windows, Mac, Android and Linux actively blocks content like ads, analytics trackers and social share buttons that may record your behavior without your knowledge across sites," Nguyen wrote.

In the video that accompanies the announcement he says, "You might notice that some web pages load more quickly with tracking protection. We don't think you'll mind."

Firefox has an add-on mechanism that has already been used by others like AdBlock Plus and the Electronic Frontier Foundation's Privacy Badger to extend the browser's functionality into this kind of blocking.

Firefox Screenshot after Tracking Protection

But Firefox is taking a different approach than a typical ad blocker. Firefox looks only for those elements (whether ads or other things) that perform user-tracking and then blocks them.

Having this feature readily available inside the browser can only increase adoption. It may be that this feature will introduce tracking blocker privacy to those that have not yet acquired the add-on extensions. The feature might even give users a reason to migrate to Firefox as their go-to browser, since it differentiates Firefox from other browsers.

"We look forward to seeing other browsers and mobile platforms follow in Firefox's footsteps. We hope that this will also send a strong message to advertisers -- if you track users nonconsensually, you're not welcome on the Net," according to an EFF statement about the release of Tracking Protection in Firefox.

To initiate tracking protection, you call up a new secure browsing window. The window comes up saying that it is activated, and it will not save history, searches, cookies, or temporary files. It does save downloads and bookmarks.

[Read Google Contributor: an Ad-Blocking Alternative.]

There is a shield icon in the left side of the URL box that confirms that you are in the correct mode. Clicking on it also confirms that it is active, and displays a button to turn the tracking off for the session. You can also access most commands through the Control Center menu at the top right of the browser bar.

Also included in Firefox 42 are security patches.

Mozilla engineers uncovered two flaws (CVE-2015-7181 and CVE-2015-7182) in NSS (which is a toolkit used by Firefox to encrypt web traffic over SSL/TLS) that could have allowed the installation of malware and an integer overflow bug (CVE-2015-7183) in NSPR, which is a component of NSS that could have done the same thing if exploited.