Contact emails victor...@chromium.org, miketa...@chromium.org
Explainer https://github.com/Tanych/accept-language Specification Variants header: https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-variants-06 Summary We want to reduce the amount of information the Accept-Language header exposes in HTTP requests and JS interface navigator.languages. Instead of sending all user’s Accept-Language, we only send the user’s most preferred language after language negotiation in the Accept-Language header. navigator.languages returns the same value as navigator.language during this experiment. We would like to run an origin trial for sites to opt into the Reduce Accept-Language origin trial to proactively test for breakage. See below for more details. Implementation Doc https://docs.google.com/document/d/1RkPDf7DNtcOj4KXeW8wNCuYfto-drnGYST_NvZe3GoY Blink component Privacy>Fingerprinting <https://bugs.chromium.org/p/chromium/issues/list?q=component:Privacy%3EFingerprinting> Risks Interoperability and Compatibility The compatibility risk is low since we're planning to reduce the amount of information in the Accept-Language header and navigator.languages, rather than remove the header or change value format in the header. Most existing Accept-Language detection code should continue to work. As for interoperability, no signal for other vendors. For multilingual sites to rely on the Accept-Language header, developers would need to depend on a user's full Accept-Language list for some browsers and a primary user's Accept-Language for others. Another signal is that the Chrome incognito model already reduced the Accept-Language header and JS interface navigator.languages to one language. The Accept-Language header can potentially expand to two if the first Accept-Language includes a region code, like en-US, the reduced Accept-Language header will be en-US,en;q=0.9. Experiment Summary The experiment is going to be a little different from a normal Origin Trial. The goal is enabling developers to test and ensure compatibility with our proposed changes. It’s incredibly important we give developers any chance to test systems at every level since this change represents vast dependencies on the introduced headers. As for enabling with the origin trial itself, there will be two components controlled by the same origin trial: - Reducing the information in navigator.languages if the origin trial enabled. - The Accept-Language HTTP request header contains the user’s primary preferred language, this can change if we detect a more preferred language during the language negotiation process. Because of the experimental nature of reducing Accept-Language, a valid origin token must be sent in the response header by origins which opt-in the origin trial. Also two new headers Variants <https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-variants-06#section-2> (indicating sites supporting languages) accept-language and Content-Language <https://datatracker.ietf.org/doc/html/rfc3282> need to be sent in the response header in order to make the language negotiation to work correctly. Please see the design and implementation document <https://docs.google.com/document/d/1RkPDf7DNtcOj4KXeW8wNCuYfto-drnGYST_NvZe3GoY/edit#heading=h.b6kmd248xsy4>for more information. Experiment Goals The goal of this origin trial is to enable developers to test how reducing the Accept-Language request header and the JS getter navigator.languages will affect their systems, especially to understand the user cases on navigator.languages. We hope this can provide sufficient time for developers to test. We can validate our current plans for reducing Accept-Language and safely roll out them to the web based on their feedback. We will be relying heavily on user and developer feedback to identify where breakage occurs, or where use cases are not accounted for, especially for multilingual sites depending on the Accept-Language header, and navigator.languages. We will create a GitHub repository and a public mailing list for gathering feedback. When the origin trial is ready, we plan to publish developer guidance on how to enroll and provide feedback. Experiment Risks There are some risks, as many multilingual sites have come to rely on the value in Accept-Language header and JS interfaces navigator.languages to send the right representation pages to the user. Site breakage can take many forms, both obvious and non-obvious. However, since sites are in control of the Origin-Trial, Variants and Content-Language headers, a site can quickly opt out of the experiment when breakage is encountered. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)? No (All but WebView) Is this feature fully tested by web-platform-tests <https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md> ? No (We fully test in browser_tests, WPT has limits to cover all the test cases in Accept-Language header). Flag name ReduceAcceptLanguageOriginTrial 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/CAJh4P7EvtPH_NQX_mJevEXu2fbePPQ7aYhfdBd%2BYB1J-5cn74g%40mail.gmail.com.
