> one extra bit

If it's the OS default, it's probably worthless. But if it isn't, I would imagine it could be quite unique, no? Presuming it's an RGB color, that's 16M possibilities. And there are multiple system colors, meaning even more chance you're a snowflake if you customized them. If you chose a random color on just 2 of them, that's probably enough to make you unique among the entire world. (But it is, of course, likely that you might choose something common, like #ff00ff.)

If you turn of JavaScript, that's also probably a pretty good signal, no? (I'm just hearing someone shouting "There are dozens of us! Dozens!")

If you turn Javascript off, the only information the website can get is user agent and IP, which would narrow it down much less than using Javascript even just among the pool of non-javascript users.

Keep in mind that there are a lot of services that load sites without Javascript enabled (scrapers, mail, preloading).

Pretty sure you can get some extra information through CSS media queries that only trigger a server hit when active (allowing you to add, say, screen size and color range to the fingerprint even without javascript).

https://stackoverflow.com/questions/53838754/css-media-queri...