Even though i have Proton VPN blocking trackers and use firefox with arkenfox EFF always says my browser has a unique fingerprint. Same with Mullvad browser and Tor. When I switched Tor to “Safer” it said near unique fingerprint, and only when i switched it to safest did it say i am protected from fingerprinting
from my results id guess that it has no fingerprit thanks to no javascript, but 90% of websites are useless without js
You choice of language already has a great impact on uniqueness. You can’t (practically) become less unique than browser wanting stuff in English.
Resolution? Might be really bad, if say you use a smartphone with 20.5:9 aspect ratio or something. Speaking of: Performance is also a factor. If your device uses a rare SoC with measurably different speed than others, that’s some uniqueness right there.
Now, you (presumably) have very strict privacy settings. That alone makes you more unique, because who really cares, right? And for example blocking region specific ads can be really, really bad in terms of uniqueness.
EFF’s website explains a bit about what they use. Refer to that to get a better idea about what makes you unique.