Browser firm says its new browser add-on will be 'a step forward in the fight for greater openness across the internet'

Mozilla has released a free tool called Lightbeam that aims to help users of the Firefox browser see who is tracking their browsing habits.

Lightbeam is a browser add-on that creates a real-time graph of all the tracking information that is deposited in the form of cookies on your computer as you browse the internet. It will enable users to identify third-party companies tracking their online behaviour for targeted advertising and other purposes.

The launch was described as a "watershed moment" by Mozilla, which is hoping to capitalise on growing awareness among internet users of how their online activities are tracked for commercial purposes. The company started work on the add-on in 2012 under the name Collusion.

Lightbeam is aimed at a mainstream audience, producing a real-time visualisation charting every site a user visits, and every third-party that operates on those sites that could be collecting and sharing user data. Mozilla is keen to stress that cookies in themselves aren't bad: it's just that internet users should be aware of who they're being used by, and for what purposes.

"Third parties are an integral part of the way the Internet works today. However, when we’re unable to understand the value these companies provide and make informed choices about their data collection practices, the result is a steady erosion of trust for all stakeholders," wrote Mozilla's privacy and public policy lead Alex Fowler in a blog post announcing Lightbeam's launch.

Facebook Twitter Pinterest Mozilla's Lightbeam allows users to identify which companies are tracking your online movements.

Crowdsourcing a ‘Wizard of Oz moment’

Lightbeam will also optionally send anonymised information about which sites and third parties are tracking your movements to Mozilla for inclusion in a crowd-sourced database of trackers, shining a light on the hidden world of data tracking and privacy.

The add-on has already been welcomed by Till Faida, co-founder of popular ad-blocking browser extension Adblock Plus. “Mozilla’s latest Lightbeam tool represents a step forward in the fight for greater openness across the internet. We are delighted to see that the industry is waking up to the demand for a more user-determined internet experience," said Faida.

"It is crucial that web users are educated on their online rights and informed about what is actually happening when they spend time online. This ensures that they are the ones in control of their online experience," said Faida.

Lightbeam will also help reveal the sources of images, scripts and adverts displayed on web pages that originate from third-party domains and service providers with the ultimate aim of identifying those that may not be necessary or welcome.

Lightbeam is an open-source tool that is available to view on Github and download direct from Mozilla.

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