Fortunately, this is entirely optional. The "privacy.resistFingerprinting" option bundles a set of features that make it more difficult for sites to uniquely id

Fortunately, this is entirely optional. The "privacy.resistFingerprinting" option bundles a set of features that make it more difficult for sites to uniquely identify the user at a cost to usability. It's up to each user to determine whether that usability cost is worth the privacy improvements. On Firefox, it's an opt-in setting, off by default.