Hello Blink owners,
We are asking for a breaking period of 3 weeks to this API, followed by a renewed experiment for the traditional 6 milestones (2024-May-14 to 2024-Jun-04). A request <https://groups.google.com/a/chromium.org/g/blink-dev/c/I4RE2pbocTg> that seems similar to me was granted in January 2022 for another API, and later shipped successfully with consensus with Mozilla and Apple. At the time of writing, we have public support <https://github.com/screen-share/meetings/blob/main/minutes/2023-02-16.md#appendix-a-poll-for-element-capture> for this API from such companies as Zoom, Jitsi, Mux, DialPad, Whereby, Intel and Tella. Tango’s co-founder wrote <https://github.com/screen-share/element-capture/issues/3#issuecomment-1483660309> “I can't emphasize enough how instrumental this specification would be for our product and user experience.” However, none of them have signed up for the OT as of yet. >From the OT perspective: This API allows Web developers to build novel new features; however, it requires a non-trivial investment. We are hoping that after giving more time, we will see more participation. >From the standardization perspective: We need time to pick up discussions with Mozilla and Apple again. As Chrome’s Security and Privacy experts do not share the concerns Mozilla and Apple have previously voiced, it stands to reason that additional discussions will allow us to converge - and we will prioritize these discussions now. Additionally, some possibilities remain for API changes that could perhaps allow for a compromise, mostly around cross-origin isolation. (Full disclosure - this is not my ideal outcome, but it’s a fallback possibility worth mentioning.) Progress made: - Spec: The spec has evolved and is now more mature, dealing better with such edge cases as loss of “eligibility for restriction.” - TAG: Previously we held off on the request for a TAG review until we got some more developer feedback about the API shape. Having received this initial feedback, the TAG request <https://github.com/w3ctag/design-reviews/issues/954> has now been submitted. - Signals: Signals have been requested. Mozilla responded. We intend to prioritize this discussion with them now. - Feedback: Outreach for feedback from the spec community - multiple issues <https://github.com/screen-share/element-capture/issues?q=is%3Aissue> were filed on the spec by Web developers. - WPT: Coverage has recently been extended <https://chromium-review.googlesource.com/c/chromium/src/+/5404107/15/third_party/blink/web_tests/external/wpt/mediacapture-streams/BrowserCaptureMediaStreamTrack-restrictTo.https.html> . Reasons to run a new trial: Gain additional feedback from new participants. Examples for remaining areas where new feedback could help include: - Uncover new edge cases which were not uncovered by the spec authors and reviewers, implementers and current OT participants. The current edge cases here <https://screen-share.github.io/element-capture/#elements-eligible-for-restriction> demonstrate how non-obvious these may be. - Validate (or refute) the assumptions we have made about the viability of an MVP that is missing some functionality. Examples: - Events notifying apps when an element stops/starts being “eligible for restriction”. - Mechanism to force elements into an “eligible for restriction” state. - Encourage future OT participation by Web developers, by demonstrating that risks associated with relying on an origin trial, while real, are partially offset by a commitment to keep the OT going until discussions conclude. Thanks, Elad On Monday, November 27, 2023 at 4:00:11 PM UTC+1 Elad Alon wrote: > Thank you for updating, Jan-Ivar. I have now updated this information in > the ChromeStatus entry. I am looking forward to carry on the discussion > about your position in your standards-positions GitHub repo, in the Element > Capture spec repo, in the Screen Capture CG and in the WebRTC WG. > > On Monday, November 27, 2023 at 3:53:51 PM UTC+1 jbru...@mozilla.com > wrote: > >> The Gecko position has been updated to negative. See >> https://github.com/mozilla/standards-positions/issues/857 >> >> On Monday, November 20, 2023 at 6:41:00 AM UTC-5 Elad Alon wrote: >> >>> Contact emails >>> >>> elad...@chromium.org >>> >>> Explainer >>> >>> https://github.com/screen-share/element-capture/blob/main/README.md >>> >>> Specification >>> >>> https://screen-share.github.io/element-capture >>> >>> Summary >>> >>> API for capturing a subtree of the DOM. >>> >>> Given a video MediaStreamTrack obtained through pre-existing means to >>> initiate tab-capture, Element Capture allows mutating the track to only >>> capture a subtree of the DOM starting at a given Element. >>> >>> The API bears some resemblance to the Region Capture API, but affords >>> greater flexibility for applications, because occluding and occluded >>> content are both excluded from the capture. >>> >>> >>> Blink component >>> >>> Blink>GetDisplayMedia >>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EGetDisplayMedia> >>> >>> TAG review >>> >>> We are holding off on the request for a TAG review until we get some >>> more developer feedback about the API shape. >>> >>> TAG review status >>> >>> Pending >>> >>> Risks >>> >>> Interoperability and Compatibility >>> >>> Gecko: Under consideration ( >>> https://github.com/mozilla/standards-positions/issues/857) >>> >>> WebKit: No signal ( >>> https://github.com/WebKit/standards-positions/issues/280) >>> >>> Web developers: >>> >>> Positive See upvotes and comments on the following: >>> >>> >>> - https://github.com/WICG/proposals/issues/73 >>> - https://twitter.com/quicksave2k/status/1583388663597015042 >>> >>> >>> Other signals: >>> >>> 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? >>> >>> >>> Goals for experimentation >>> >>> * Solicit more informed Web developer feedback to validate the API shape. >>> >>> * Ensure that the feature works correctly in conjunction with adjacent >>> features. >>> >>> >>> Debuggability >>> >>> No changes to DevTools are intended. >>> >>> >>> Will this feature be supported on all six Blink platforms (Windows, Mac, >>> Linux, Chrome OS, Android, and Android WebView)? >>> >>> No >>> >>> This API is supported on all desktop platforms. Mobile platforms are >>> unsupported because screen-capture itself is unsupported on those platforms. >>> >>> >>> Is this feature fully tested by web-platform-tests >>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >>> ? >>> >>> Not yet (but we’re working on extending coverage) >>> >>> Flag name on chrome://flags >>> >>> element-capture >>> >>> Finch feature name >>> >>> ElementCapture >>> >>> Tracking bug >>> >>> https://bugs.chromium.org/p/chromium/issues/detail?id=1418194 >>> >>> Launch bug >>> >>> https://launch.corp.google.com/launch/4240472 >>> >>> Estimated milestones >>> >>> Shipping on desktop >>> >>> 121 >>> >>> >>> Link to entry on the Chrome Platform Status >>> >>> https://chromestatus.com/feature/5198989277790208 >>> >>> Links to previous Intent discussions >>> >>> Intent to prototype: >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAMO6jDO6y5b6y3q9QEd2scsYPWuWLJBnPLgwm%2BaHpKx36CYMwA%40mail.gmail.com >>> >>> 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. 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