New Firefox to Block Unwanted Tracking, Cryptojacking

John Lister's picture

Firefox is getting a series of updates to boost performance, privacy and usability. Unwanted tracking tools and browser hijackers are among the targets of security updates.

Two of the biggest measures deal with websites that track user activity online, potentially to make site content more relevant, but more commonly to deliver targeted advertising.

Version 63 of Firefox, due in September, will by default block ad trackers if they take a particularly long time to load, in turn making pages slow to appear. This setting is purely to do with the load time of the tracker rather than what it actually does.

Browser Could Block Cryptojacking

Firefox version 63 may also get a block on cryptojacking, as long as a current test program works out. Cryptojacking is where a website hijacks a computer's resources and uses them remotely to try to verify transactions in a blockchain, which is the digital "ledger" used to keep track of virtual currencies such as Bitcoin.

This can be lucrative as the first person to complete a batch of verifications is rewarded with a payment in the currency that can be sold for real-world cash. Cryptojacking is bad news for the victims as it means their machine may slow down or overheat. (Source:

Another change tentatively scheduled for version 63 is a suggested extensions tool, known formally as a "Contextual Feature Recommender." This will look at the contents of a website and suggest any relevant extensions. It appears they'll mainly be official extensions produced by the website in question.

'Fingerprinting' In Mozilla's Sights

Version 65, which should follow in January, will by default block cross-site trackers. These monitor a user's activity even after they have left the site in question. That lets them build up a better picture of the user's interests, which can affect the content and ads they see if and when they return to the site.

At some point Mozilla also plans to have Firefox block 'fingerprinting' by default. That's where trackers try to identify an individual computer to make tracking easier. They do this by combining multiple pieces of information about the PC that are accessible to websites such as time zone, screen resolution, and what versions of particular software are running. The idea is to combine so many factors that the pattern of a specific computer is unique. (Source:

What's Your Opinion?

Is Firefox right to block slow or cross-site trackers by default? Do such moves make you more likely to use such a site? Do you pay much attention to 'behind the scenes' tools in browsers?

Rate this article: 
Average: 5 (14 votes)