Currently, Mozilla has been enhanced in standard mode tracking protection in Firefox 72 Nightly enabled "fingerprint reader" option is enabled standard content blocking mode by default, when the user is online, will be protected from fingerprints script s attack. Firefox 72 scheduled for release in 2020 January 7.
The current stable version of Firefox 70 has a standard mode prevents social media tracker , cross-site tracking cookie, the default trace window in the private content and Cryptominer case.
Some sites based on the user's system configuration, screen resolution, using a browser, installed fonts to its composition, this is known as fingerprint recognition, when the user selects the "strict" or enable the "fingerprint reader" in Custom mode , Firefox can use the "enhanced tracking protection," to defend against such a script.
Reference News: https://techdows.com/2019/11/mozilla-firefox-72-nightly-now-blocks-fingerprinting-scripts-by-default.html