Instead of Randomizing fingerprint , if Firefox set a default(same for all users) fingerprint for canvas, audio,screen size , webgl ,font and timezone to all Firefox user . It will give better protection against fingerprint tracking .
I like this idea and it reads like Safari's fingerprint defense, which isn't a bad thing.
"To combat fingerprinting, Safari presents a simplified version of the system configuration so more devices look identical to trackers, making it harder to single yours out. This protection is on by default, so there are no extra steps for you to take."