Updated the explainer. Pls review. Thanks, Suresh
From: Alex Russell <[email protected]> Sent: Wednesday, September 10, 2025 8:44 PM To: blink-dev <[email protected]> Cc: Yoav Weiss <[email protected]>; [email protected] <[email protected]>; Suresh Potti <[email protected]>; Chromestatus <[email protected]> Subject: [EXTERNAL] Re: [blink-dev] Intent to Ship: FedCM—Support Structured JSON Responses from IdPs You don't often get email from [email protected]<mailto:[email protected]>. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> I like the change, but the linked "explainer" doesn't cover the ground we expect to see. Can you please draft a separate document for this feature and address questions raised in the GH thread in that doc? Thanks, Alex On Tuesday, September 9, 2025 at 5:33:34 AM UTC-7 Yoav Weiss wrote: LGTM1 This seems like a small yet useful addition. On Sat, Sep 6, 2025 at 5:51 AM Chromestatus <[email protected]<mailto:[email protected]>> wrote: Contact emails [email protected]<mailto:[email protected]> Explainer https://github.com/w3c-fedid/idp-registration/issues/13#issuecomment-3254858070 Specification https://github.com/w3c-fedid/FedCM/pull/771 Summary Allows Identity Providers (IdPs) to return structured JSON objects instead of plain strings to Relying Parties (RPs) via the id_assertion_endpoint. This change simplifies integration for developers by eliminating the need to manually serialize and parse JSON strings. It enables more dynamic and flexible authentication flows, allowing RPs to interpret complex responses directly and support varied protocols like OAuth2, OIDC, or IndieAuth without out-of-band agreements. Blink component Blink>Identity>FedCM<https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EIdentity%3EFedCM%22> Web Feature ID fedcm<https://webstatus.dev/features/fedcm> TAG review https://github.com/w3ctag/design-reviews/issues/1147 TAG review status Issues open Risks Interoperability and Compatibility None Gecko: No signal comments from Ben Vandersloot in https://github.com/w3c-fedid/meetings/blob/main/2025/2025-07-29-FedCM-notes.md#status-of-cr-blockers, No strong opinions WebKit: No signal Web developers: Positive Other signals: This was requested by Identity providers. Ergonomics n/a Activation n/a Security n/a WebView application risks Does this intent deprecate or change behavior of existing APIs, such that it has potentially high risk for Android WebView-based applications? n/a, FedCM not supported in WebView Debuggability Same as other FedCM features. The network view in devtools would be especially helpful for debugging this feature. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)? No FedCM in general is not supported on webview. Supported on all other blink platforms. Is this feature fully tested by web-platform-tests<https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>? Yes https://wpt.fyi/results/fedcm/fedcm-flexible-token?label=experimental&label=master Flag name on about://flags None Finch feature name FedCmNonStringToken Rollout plan Will ship enabled for all users Requires code in //chrome? False Tracking bug https://issues.chromium.org/346567168 Estimated milestones Shipping on desktop 143 Shipping on Android 143 Anticipated spec changes Open questions about a feature may be a source of future web compat or interop issues. Please list open issues (e.g. links to known github issues in the project for the feature specification) whose resolution may introduce web compat/interop risk (e.g., changing to naming or structure of the API in a non-backward-compatible way). none Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5153509557272576?gate=5128781719273472 This intent message was generated by Chrome Platform Status<https://chromestatus.com/>. -- 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 [email protected]<mailto:[email protected]>. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/68bbafb9.050a0220.257801.01b2.GAE%40google.com<https://groups.google.com/a/chromium.org/d/msgid/blink-dev/68bbafb9.050a0220.257801.01b2.GAE%40google.com?utm_medium=email&utm_source=footer>. -- 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 [email protected]. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/TYZP153MB1077242D2E7FE75E3FF84533BD1EA%40TYZP153MB1077.APCP153.PROD.OUTLOOK.COM.
