European group accuses Mozilla Firefox browser of tracking users’ activities without consent

A European digital rights organization, None of Your Business (NOYB) has filed a formal complaint against Mozilla, the company behind the popular privacy-focused web browser Firefox, for quietly rolling out a new tracking feature in its latest version update.  

The feature, called Privacy-Preserving Attribution (PPA), turned the browser into a tracking tool for websites without directly telling its users.  

NOYB argued that the new feature infringes on users’ rights under the European Union’s General Data Protection Regulation (GDPR). 

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According to Mozilla, PPA is designed to help websites understand the effectiveness of their ads without collecting personal data. Instead, it aggregates user data in larger groups to identify trends. 

Key concerns

NOYB’s main argument is that although PPA does not collect data on individuals, it still enables tracking of user behavior across websites.  

• This form of tracking, according to NOYB, does not replace cookies but introduces a new method for advertisers to target users without their explicit consent. 

• A major sticking point in the complaint is Mozilla’s decision to activate PPA by default when users update to Firefox version 128.  

• According to NOYB, users were not informed about the new tracking mechanism, nor were they given the option to opt in.  

• The organization has accused Mozilla of failing to include the feature in its data protection policies, making it difficult for users to fully understand how their data is being processed. 

“It’s a shame that an organization like Mozilla believes that users are too dumb to say yes or no. Users should be able to make a choice and the feature should have been turned off by default,” said Felix Mikolasch, data protection lawyer at NOYB. 

Mozilla’s defense 

Mozilla’s Chief Technology Officer, Bobby Holley, responded to the growing concerns, admitting that the company should have communicated the change more effectively.  

On Reddit, Holley defended the introduction of PPA, saying that Mozilla’s goal is to tackle the pervasive issue of web surveillance without resorting to invasive tracking practices.  

He emphasized that PPA was designed to strike a balance between advertisers’ needs and user privacy, offering a less intrusive alternative to the current methods of data collection used by many websites. 

In a bid to reassure users, Holley mentioned that there is a toggle option to disable the PPA feature. He stated, “We support people configuring their browser however they choose,” underscoring that Mozilla remains committed to giving users control over their online experience. 

What you should know

While the data privacy concern is being raised in Europe, the infringement affects users of the browser globally.  

• According to a report by SEO platform, Backlinko, Mozilla Firefox had around 178 million users worldwide As of February 2024.  

• That gave the browser 3.36% of the market share in a space dominated by Google Chrome (65.23%).  

• Open-source Firefox was once a top browser choice among users due to its privacy features but now trails market leader Google’s Chrome, Apple’s Safari, and Microsoft’s Edge with a low single-digit market share.