BrowsersWorkspace

Mozilla Disables Battery Tracking API To Tighten Firefox Privacy

Tom Jowitt is a leading British tech freelance and long standing contributor to TechWeek Europe

Firefox cuts off support for API that allows websites to detect user battery levels over tracking fears

Mozilla has disabled an API in Firefox over concerns it could be used to track users.

It comes after Mozilla mulls the extension of Firefox’s Track Protection, which it introduced more than a year ago.

Battery Tracking

However Mozilla’s latest decision to disable the ability of websites to access the Battery Status API in Firefox 52, comes after warnings from security researchers that the feature could allow the user to be tracked.

In August researchers from Princeton University found that the Battery Status API, a feature first introduced in HTML5 in 2012, allows websites and apps to see, without a permission request, the amount of juice a visiting user has remaining on their device, and decide to serve a less power intensive version of the site if required.

The API also displays whether the user’s device is plugged in and charging, how long the battery will last, and the percentage of charge remaining.

Unfortunately, the researchers also found this API was being used by trackers as a ‘fingerprinting vector’. Essentially, tracking scripts were using the API to ‘fingerprint’ devices, thereby gaining the ability to track that device’s web habits.

Now Mozilla has opted to disable this API for Firefox 52 and onwards.

Rival web browsers Chrome and Opera also reportedly support this Battery Status API, but Microsoft’s Edge and Internet Explorer browsers do not support it. Neither apparently does Apple’s Safari.

Native Ad Blocking

Mozilla last month also revealed that it could add a degree of native ad blocking to Firefox in a future release, if a test of the ‘Tracking Protection’ feature in the browser is successful.

It is encouraging users to participate in the trial.

Firefox, alongside Google’s Chrome, also recently started to try and block direct access to The Pirate Bay’s download pages, displaying warnings to users rather than a page of torrents.

Back in May, both companies took steps to block ThePirateBay.se domain; but both browsers still allow their users to navigate to the popular torrent website, despite the warnings.

That move came amid concerns that behind The Pirate Bay sits an advertising network that has malware or has been infected by it.

Are you a Firefox fan? Try our quiz!