Mozilla update aims to reduce digital fingerprinting vulnerability

Mozilla is rolling out expanded anti-fingerprinting defenses in Firefox 145, debuting first in Private Browsing Mode and in Enhanced Tracking Protection's Strict setting, BleepingComputer reports.

The update introduces a new round of privacy measures that will later become the browser's default. Mozilla says its earlier anti-fingerprinting efforts, which started in 2021, lowered user trackability from about 65% to roughly 35% by restricting access to indicators such as graphics behavior, small mathematical differences, and installed fonts.

The new "Phase 2" protections block attempts to read local fonts, hardware details, touch capabilities, processor core counts, and dock or taskbar dimensions. They also enforce standardized outputs, including always reporting two CPU cores and reducing available screen height by 48 pixels.

According to Mozilla, these steps bring unique fingerprinting down to about 20% of users. The organization warns that completely eliminating signals would break legitimate site functions, and users can disable the new protections on specific pages if needed.