reduce-accept-language

Some time ago I noticed that in Chrome, every time you click "Never translate $language", $language quietly gets added to the Accept-Language header that Chrome sends to every website! My header ended up looking like a permuted version of this: en-US,en;q=0.9,zh-CN;q=0.8,de;q=0.7,ja;q=0.6 I never manually configured any of those extra languages in the browser settings. All I had done was tell Chrome not to translate a few pages on some foreign news sites. Chrome then turned those one-off choices into persistent signals attached to every request. I'd be surprised if anyone in my vicinity share my exact combination of languages in that exact order, so this seems like a pretty strong fingerprinting vector. There was even a proposal to reduce this surface area, but it wasn't adopted: https://github.com/explainers-by-googlers/reduce-accept-