STOCKHOLM, Sept 25 (Reuters) - Vienna-based advocacy group NOYB on Wednesday said it has filed a complaint with the Austrian data protection authority against Mozilla accusing the Firefox browser maker of tracking user behaviour on websites without consent.

NOYB (None Of Your Business), a digital rights group founded by privacy activist Max Schrems, said Mozilla has enabled a so-called privacy preserving attribution (PPA) feature that turned the browser into a tracking tool for websites without directly telling its users.

“Mozilla's limited test of PPA is a part of our effort to improve invasive advertising practices by providing technical alternatives,” a spokesperson told Reuters. “These techniques prevent any party, including Mozilla, from identifying individuals or their browsing activity.”

While this may be less invasive than unlimited tracking, it still interferes with user rights under the EU’s privacy laws, NOYB said, adding that Firefox has turned on the feature by default.