Mozilla is the latest company to get in trouble with the EU. Austrian advocacy group Noyb has filed a complaint against Mozilla for setting a Privacy Preserving Attribution (PPA) feature to default without informing its users. Noyb claims the setting impacts millions of Europeans.

According to Mozilla, PPA involves websites asking Firefox to remember ads they show and to potentially generate an interest report. Firefox creates the data but then submits it to an aggregation service, where the report is combined with similar ones. The company claims individual’s browsing activity isn’t shared with any third-parties, making it a safer system.

Noyb’s complaint alleges that this still interferes with EU users’ GDPR-confirmed rights — while taking a dig at widespread tracking being the “norm” in the US. “Mozilla has just bought into the narrative that the advertising industry has a right to track users by turning Firefox into an ad measurement tool,” said Felix Mikolasch, a data protection lawyer at Noyb, in a statement. “While Mozilla may have had good intentions, it is very unlikely that ‘privacy preserving attribution’ will replace cookies and other tracking tools. It is just a new, additional means of tracking users.” Users wanting to turn PPA off must navigate to the browser’s settings and click opt-out in a sub-menu.

The complaint ends with Noyb requesting that the Austrian data protection authority investigates Mozilla’s privacy settings. It also states that Mozilla should alert users about its data processing steps, use an opt-in system and delete “unlawfully” processed data. Noyb has previously lodged complaints against tech companies such as Microsoft, Meta and OpenAI.