[jimbobthrowawy]

If you're in a region that google defaults to another language, &hl=en (or another language code) is very useful. Nowadays I mainly use it for the maps site, but I've used it elsewhere before when I couldn't struggle through a website in another language. It's very hard to get it into certain google products, like recaptcha. So I have to learn the words for what it wants clicked.

I don't know if parsing the Accept-Language header is too slow, or if google's trying to encourage people to log in to an account.

[ekimekim]

From what I've heard, Google purposely ignores the Accept-Language header because they believe browsers with a mis-configured language (eg. the browser is set to use english when the user doesn't want english) is more common than browsers with a correctly configured language that differs from their geoip location (eg. someone in France who wants to view a site in english).

[jimbobthrowawy]

That was my guess too. I haven't checked if they ignore it for all languages, or just English.

I remember being very confused when another site (wttr.in) would show up in Russian on a friend's computer for some reason. I later learned that clicking "never translate <language>" back then in chrome's prompt to translate would add that language to the Accept-Language header. The site then served this version, despite en-ie and en being higher priority.