In my case the single largest contributor to my fingerprint is ... canvas size. I run full screen with a custom Firefox setup that basically makes my canvas size unique :/ The "protection" Firefox uses for this is to always open a new window at a default size, which does nothing in my case since my toolbar config still makes the canvas size unique.
It would be really useful to have something that dithers the reported canvas size by 5 or 10 pixels in different containers to add noise there.
Doesn't seem to work... reported canvas size is still some odd value (2200x1283x24). I think it uses a fixed size for the letterbox, which is useless. Right general idea though.
Now I understand why I'm getting paywall limits even in private browsing :) I use Tree Style Tab, so my canvas is also of unusual size and ratio. I guess I can try making it more narrow or wider to combat that :)
It would be really useful to have something that dithers the reported canvas size by 5 or 10 pixels in different containers to add noise there.