Thanks for the response! Yes, we will be keeping an eye on metrics and bug reports.
In terms of the character set, it is defined here: https://wicg.github.io/ua-client-hints/#create-arbitrary-brands-section It includes: 0x20 (SP), 0x28 (left parenthesis), 0x29 (right parenthesis), 0x2D (-), 0x2E (.), 0x2F (/), 0x3A (:), 0x3B (;), 0x3D (=), 0x3F (?), 0x5F (_). The prior implementation included only space (0x20) and semicolon (0x3B). On Tue, Feb 1, 2022 at 4:45 AM Mike West <mk...@chromium.org> wrote: > LGTM to experiment with this change on a small percentage of stable in M98 > and M99. Presumably you'll be keeping an eye on metrics and bug reports to > roll it back in case unexpected incompatibility is discovered. > > Out of curiosity, what is the new character set with which you'll be > working? The spec link was fairly generic, describing a strategy rather > than an algorithm. > > -mike > > On Wednesday, January 26, 2022 at 11:18:56 PM UTC+1 Matt Reichhoff wrote: > >> Contact emails >> >> mreichh...@chromium.org, miketa...@chromium.org, jadekess...@chromium.org >> >> Explainer >> >> https://github.com/WICG/ua-client-hints#user-agent-client-hints >> >> Specification >> >> https://wicg.github.io/ua-client-hints/#grease >> >> Summary >> >> We seek to align our implementation of GREASE in User Agent Client Hints >> with the current spec, which includes additional GREASE characters beyond >> the current semicolon and space, and which recommends varying the arbitrary >> version. This is to help prevent bad assumptions from being built on top of >> User-Agent strings. >> >> This intent seeks approval to begin an experiment on stable at 1% with >> the m98 release. Due to a clerical error, the experiment is already running >> on m98 in beta. The goal is to determine whether the new spec is web >> compatible via a controlled experiment before we ship to stable. >> >> >> Blink component >> >> Privacy>Fingerprinting >> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Privacy%3EFingerprinting> >> >> TAG review >> >> https://github.com/w3ctag/design-reviews/issues/640 >> >> TAG review status >> >> In progress, but all raised issues addressed. >> >> Risks >> Interoperability and Compatibility >> >> The prior inclusion (in 2020) of escaped ASCII 0x22 (double quote) and >> 0x5C (backslash) proved to be web incompatible and was rolled back. While >> we do not anticipate similar problems with the updated character list, we >> have taken (or will take) the following actions to validate this assumption: >> >> - >> >> Pre-launch testing of the new characters against known-common sites, >> which will include tests against the components known to have been >> incompatible with the prior implementation [COMPLETED]. >> - >> >> Addition of an enterprise policy escape hatch [COMPLETE]. >> - >> >> A phased rollout along with monitoring of HTTP 4XX response rates >> [PROPOSED HERE]. >> >> >> Gecko: Non-harmful ( >> https://mozilla.github.io/standards-positions/#ua-client-hints) >> >> WebKit: No signal >> >> Web developers: No signals >> >> Other signals: N/A >> >> >> Goals for experimentation >> >> A phased rollout is desired to ensure the changes to the spec are >> web-compatible. To that end, we will begin with 1% of users on stable, with >> monitoring of HTTP response codes to ensure the change is non-breaking. >> >> >> Debuggability >> >> N/A; no change required >> >> >> Will this feature be supported on all six Blink platforms (Windows, Mac, >> Linux, Chrome OS, Android, and Android WebView)? >> >> No (not on WebView or iOS) >> >> Is this feature fully tested by web-platform-tests >> <https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md> >> ? >> >> Yes >> <https://chromium-review.googlesource.com/c/chromium/src/+/3225903/6/third_party/blink/web_tests/external/wpt/html/webappapis/system-state-and-capabilities/the-navigator-object/navigator_user_agent.https.html> >> >> Flag name >> >> --enable-features="GreaseUACH:updated_algorithm/true" >> >> Tracking bug >> >> https://bugs.chromium.org/p/chromium/issues/detail?id=1164423 >> >> Estimated milestones >> >> We anticipate this experiment starting in M98 and running for 2 >> milestones, but it could extend if the data is inconclusive. We are most >> concerned about website tail behavior with this change, which can make data >> gathering slower than we’d like. >> >> >> Link to entry on the Chrome Platform Status >> >> https://chromestatus.com/feature/5630916006248448 >> >> Links to previous Intent discussionsIntent to prototype: >> https://groups.google.com/a/chromium.org/g/blink-dev/c/ueudFsZzT1M >> > -- 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/CAGg35awK7zU8Vi0yEAFhnfXFZ00iUq5XxO58Bv5unJyoRx94OA%40mail.gmail.com.
