The browser will only do language negotiation if necessary. Yea, you are right, it would take an extra round trip in some cases. We also plan to save some selections in memory to avoid introducing large latency.
On Sunday, May 22, 2022 at 12:11:23 PM UTC-4 Harald Alvestrand wrote: > So one extra round trip per page? > > > On Sun, May 22, 2022 at 5:31 PM Victor Tan <victor...@chromium.org> wrote: > >> Hi Harald, >> The browser will do language negotiation with resend the request (only >> happen once) with accept-language:en to get a result with English page. >> >> Victor >> >> On Saturday, May 21, 2022 at 8:38:47 AM UTC-4 Harald Alvestrand wrote: >> >>> So if my config is (no, en), the site supports (fr, en), the first >>> response will be in French with a Vary:(fr, en) header? Will the browser >>> automatically detect that a better alternative is available and re-ask, >>> imposing an extra RTT, or will the result remain French? >>> >>> fre. 20. mai 2022, 19:11 skrev 'Victor Tan' via blink-dev < >>> blink-dev@chromium.org>: >>> >>>> NOTES: This intend won't implement Variants in the HTTP cache. It only >>>> focus on using Variants http header as a support-languages head which in >>>> the definition on section 2 >>>> <https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-variants-06#section-2> >>>> . >>>> >>>> On Thursday, May 19, 2022 at 10:20:29 AM UTC-4 vict...@chromium.org >>>> wrote: >>>> >>>>> Contact emails >>>>> >>>>> vict...@chromium.org, abe...@chromium.org >>>>> >>>>> Explainer >>>>> >>>>> >>>>> https://github.com/Tanych/accept-language >>>>> Specification >>>>> >>>>> Variants header: >>>>> https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-variants-06 >>>>> >>>>> Summary >>>>> >>>>> Support the HTTP Variants header and implement the reduction of >>>>> information that could be used for fingerprinting in the Accept-Language >>>>> header, so that Chrome only sends the user’s most preferred language in >>>>> the >>>>> Accept-Language header on the initial request. >>>>> Blink component >>>>> >>>>> Privacy>Fingerprinting >>>>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Privacy%3EFingerprinting> >>>>> >>>>> Motivation >>>>> >>>>> >>>>> The Accept-Language header is a source of passive fingerprinting >>>>> information about users, as it can contain a high degree of entropy, >>>>> particularly if the user has many accepted languages. >>>>> >>>>> Chrome (and other browsers) send a full list of the user's accepted >>>>> languages on every HTTP request via the Accept-Language header. While >>>>> some >>>>> sites use this information for content negotiation, servers can also >>>>> passively capture this information without the user's awareness, to >>>>> fingerprint a user. >>>>> >>>>> We propose to only send a single language—one of the user’s preferred >>>>> languages determined by the language negotiation process—in the >>>>> Accept-Language request header by default. Here’s what that would look >>>>> like >>>>> when a user tries to access https://example.com: >>>>> >>>>> Get / HTTP/1.1 >>>>> >>>>> Host: example.com >>>>> >>>>> Accept-Language: en >>>>> >>>>> HTTP/1.1 200 OK >>>>> >>>>> Content-Language: en >>>>> >>>>> Vary: Accept-Language >>>>> >>>>> Variants: Accept-Language=(en) >>>>> >>>>> As the response shows, in addition to the Content-Language in the >>>>> response header, sites will respond with a Variants >>>>> <https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-variants-06> >>>>> header (support for which will be prototyped as part of this intent), the >>>>> value of which includes all the languages the site supports. Browsers can >>>>> use the Variants header to do language negotiation if sites offer a page >>>>> in >>>>> a language that doesn’t match the user's preferred languages. Initial >>>>> public proposal >>>>> >>>>> >>>>> https://discourse.wicg.io/t/proposal-reduce-fingerprinting-in-the-accept-language-header/5835 >>>>> >>>>> >>>>> >>>>> TAG review >>>>> >>>>> To be filed. >>>>> >>>>> RisksInteroperability and Compatibility >>>>> >>>>> We are reducing the number of languages sent in the Accept-Language >>>>> header to protect user privacy. The main source of risk is that sites >>>>> rely >>>>> on all or part of a user’s preferred languages instead of the most >>>>> preferred language. We feel it’s important to minimize the breakage of >>>>> the >>>>> features depending on Accept-Language as much as possible, to maintain >>>>> stability of the web ecosystem. To mitigate the risk of this change, we >>>>> intend to gradually roll it out via Finch configuration and keep >>>>> monitoring >>>>> health metrics and bug reports from the community. >>>>> >>>>> Gecko: No signals >>>>> >>>>> WebKit: No signals >>>>> >>>>> Web developers: See the explainer for details. >>>>> Debuggability >>>>> >>>>> No special DevTools support needed. >>>>> >>>>> Is this feature fully tested by web-platform-tests >>>>> <https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md> >>>>> ? >>>>> >>>>> It will be. >>>>> >>>>> Flag name >>>>> >>>>> reduce-accept-language >>>>> >>>>> >>>>> Requires code in //chrome? >>>>> >>>>> False >>>>> >>>>> Tracking bug >>>>> >>>>> https://bugs.chromium.org/p/chromium/issues/detail?id=1306905 >>>>> >>>>> >>>>> *Launch bug* >>>>> https://bugs.chromium.org/p/chromium/issues/detail?id=1307484 >>>>> >>>>> *Link to entry on the Chrome Platform Status* >>>>> https://chromestatus.com/feature/5188040623390720 >>>>> <https://chromestatus.com/feature/5188040623390720#details> >>>>> >>>>> >>>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "blink-dev" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to blink-dev+unsubscr...@chromium.org. >>>> To view this discussion on the web visit >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/12b25cad-3902-4a09-bd9c-3c30a3b41ab6n%40chromium.org >>>> >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/12b25cad-3902-4a09-bd9c-3c30a3b41ab6n%40chromium.org?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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