Intent to Experiment: Conditional Focus

Elad Alon

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Sep 22, 2021, 3:16:59 PM9/22/21

to blink-dev

Summary

Extend the getDisplayMedia APIs to ensure that tab-capture and window-capture return a new subclass of MediaStreamTrack called FocusableMediaStreamTrack. This new subclass exposes the focus() method. This new method allows Web-applications, when capture starts, to decide whether the captured tab/window should be immediately focused, or whether the capturing tab+window should remain the focused one.

Blink component

Blink

TAG review

https://github.com/w3ctag/design-reviews/issues/679

TAG review status

Pending

Risks

Interoperability and Compatibility

Gecko: No signal

WebKit: No signal

Web developers: No signals

Ergonomics

N/A

Activation

Not challenging - just feature-detect: // Pre-existing functionality: let mediaStream = await navigator.mediaDevices.getDisplayMedia(); let [track] = mediaStream.getVideoTracks(); // New functionality behind feature-detection: if (!!track.focus) { track.focus(...); }

Security

See design-doc.

Goals for experimentation

Reason this experiment is being extended

Ongoing technical constraints

Debuggability

N/A

Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)?

No

Supported on all Desktop platforms.

Is this feature fully tested by web-platform-tests?

No

Flag name

ConditionalFocus

Requires code in //chrome?

True

Tracking bug

https://bugs.chromium.org/p/chromium/issues/detail?id=1215480

Launch bug

https://bugs.chromium.org/p/chromium/issues/detail?id=1214483

Estimated milestones

m96

Link to entry on the Chrome Platform Status

https://www.chromestatus.com/feature/5646614535340032

Links to previous Intent discussions

Intent to prototype: https://groups.google.com/a/chromium.org/g/blink-dev/c/lbuqOGx07xY

This intent message was generated by Chrome Platform Status.

Yoav Weiss

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Sep 23, 2021, 3:31:04 PM9/23/21

to Elad Alon, blink-dev

On Wed, Sep 22, 2021 at 2:16 PM 'Elad Alon' via blink-dev <[email protected]> wrote:

Contact emails
[email protected]

Explainer
https://github.com/eladalon1983/conditional-focus/blob/main/README.md

Specification
https://eladalon1983.github.io/conditional-focus/

Might be good to move this to WICG to facilitate contributions (given support).

Design docs

https://docs.google.com/document/d/1LHJRt-ry9hwzFTbPxKrmD0VvtEFEU6lvqsD7k6wwGKM/

Summary
Extend the getDisplayMedia APIs to ensure that tab-capture and window-capture return a new subclass of MediaStreamTrack called FocusableMediaStreamTrack. This new subclass exposes the focus() method. This new method allows Web-applications, when capture starts, to decide whether the captured tab/window should be immediately focused, or whether the capturing tab+window should remain the focused one.

Blink component
Blink

TAG review
https://github.com/w3ctag/design-reviews/issues/679

TAG review status
Pending

Risks

Interoperability and Compatibility

Gecko: No signal

WebKit: No signal

Web developers: No signals

https://github.com/WICG/proposals/issues/37#issuecomment-920673070 seems like a positive signal (even if from a single partner).

Ergonomics
N/A

Activation
Not challenging - just feature-detect: // Pre-existing functionality: let mediaStream = await navigator.mediaDevices.getDisplayMedia(); let [track] = mediaStream.getVideoTracks(); // New functionality behind feature-detection: if (!!track.focus) { track.focus(...); }

Security
See design-doc.

Goals for experimentation

What are the goals for the experiment?

Reason this experiment is being extended

Ongoing technical constraints

Debuggability
N/A

Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)?
No
Supported on all Desktop platforms.

Is this feature fully tested by web-platform-tests?
No

Flag name
ConditionalFocus

Requires code in //chrome?
True

Tracking bug
https://bugs.chromium.org/p/chromium/issues/detail?id=1215480

Launch bug
https://bugs.chromium.org/p/chromium/issues/detail?id=1214483

Estimated milestones
m96

What are the timeframes for the experimentation? Do you have partners lined up?

Link to entry on the Chrome Platform Status
https://www.chromestatus.com/feature/5646614535340032

Links to previous Intent discussions
Intent to prototype: https://groups.google.com/a/chromium.org/g/blink-dev/c/lbuqOGx07xY

This intent message was generated by Chrome Platform Status.

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Elad Alon

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Sep 23, 2021, 4:00:47 PM9/23/21

to blink-dev, [email protected], blink-dev, Elad Alon

Might be good to move this to WICG to facilitate contributions (given support).

WICG issue #37 asked for this to be adopted by the WICG. (The same partner supported it there too, btw.)

https://github.com/WICG/proposals/issues/37#issuecomment-920673070 seems like a positive signal (even if from a single partner).

Yes. And Mozilla and Apple also seemed interested in the use-case during the WebRTC Working Group interim meeting of September 2021, although we're still discussing the specific details.

What are the goals for the experiment?

Validate that the proposed API solves developers' issues in a satisfactory manner.

What are the timeframes for the experimentation? Do you have partners lined up?

Two internal (Google), one external (Tella).

Yoav Weiss

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Sep 23, 2021, 4:53:14 PM9/23/21

to Elad Alon, blink-dev

What's the end milestone you're targeting?

Elad Alon

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Sep 23, 2021, 5:04:25 PM9/23/21

to Yoav Weiss, blink-dev

m99, inclusive. So four milestones in total.

Yoav Weiss

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Sep 23, 2021, 5:16:42 PM9/23/21

to Elad Alon, blink-dev

LGTM to experiment M96-M99 inclusive

On Thu, Sep 23, 2021 at 4:04 PM Elad Alon <[email protected]> wrote:

m99, inclusive. So four milestones in total.

On Thu, Sep 23, 2021 at 3:53 PM Yoav Weiss <[email protected]> wrote:

On Thu, Sep 23, 2021 at 3:00 PM Elad Alon <[email protected]> wrote:
Might be good to move this to WICG to facilitate contributions (given support).

WICG issue #37 asked for this to be adopted by the WICG. (The same partner supported it there too, btw.)

<WICG-hat> Ping me and we'll move it over! :) </WICG-hat>

Elad Alon

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Jan 20, 2022, 2:04:58 PM1/20/22

to blink-dev, [email protected], blink-dev, Elad Alon

The partner I had for this feature had a change of scheduling, and will only be set to deploy their test use of it in about a month. I would therefore like to reset this experiment, stopping it for 3 weeks and then starting it afresh in m99-m102 (inclusive). Wdys?

Relevant: Discussions about standardizing this feature are proceeding and there seems to be interest from Mozilla and Apple. See here.

Mike West

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Jan 26, 2022, 8:00:51 PM1/26/22

to blink-dev, Elad Alon, Yoav Weiss, blink-dev

Hey Elad!

Did anyone at all use this feature via the OT? If so, it would be helpful to understand whether you had any feedback that would inform this new experiment.

If no one used it at all, then this really would be a no-op, and I think we'd happily approve shifting the milestones.

-mike

Elad Alon

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Jan 31, 2022, 1:22:32 PM1/31/22

to blink-dev, [email protected], Elad Alon, [email protected], blink-dev

My partners for this feature have not yet been able to take advantage of it, due to scheduling constraints on their end, and so could not yet file feedback.

I don't see feedback from anyone else.

Daniel Bratell

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Jan 31, 2022, 2:21:48 PM1/31/22

to Elad Alon, blink-dev, [email protected], [email protected]

LGTM to shift to M99-M102. Hope you can get some good feedback.

/Daniel

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Elad Alon

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Jun 8, 2022, 10:58:21 AM6/8/22

to blink-dev, Daniel Bratell, [email protected], [email protected], Elad Alon

Hello all,

Due to the scheduling constraints of my partners, this origin trial was not used in m99-m101. But my partners ready to use it now in m102, and are eager to start teamfood and dogood right away. However, m102 only has two more weeks to go, so that would be a very short trial. I am therefore asking that the experiment period be shifted from m99-m102 (inclusive), to m102-m105 (inclusive).

The use-counters on the feature show that it's only been used a mere 75 times in the last 28 days (data from 2022-06-05). I am therefore asking that shifting the experiment's time window will happen without a breaking period.

Thanks,
Elad

Yoav Weiss

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Jun 8, 2022, 11:13:23 AM6/8/22

to Elad Alon, blink-dev, Daniel Bratell, [email protected]

Seems fine to shift the experimental period. No further LGTMs needed.

On Wed, Jun 8, 2022 at 9:58 AM Elad Alon <[email protected]> wrote:

Hello all,

Due to the scheduling constraints of my partners, this origin trial was not used in m99-m101. But my partners ready to use it now in m102, and are eager to start teamfood and dogood right away. However, m102 only has two more weeks to go, so that would be a very short trial. I am therefore asking that the experiment period be shifted from m99-m102 (inclusive), to m102-m105 (inclusive).

The use-counters on the feature show that it's only been used a mere 75 times in the last 28 days

Unfortunate (but understandable) that this is a Google-only link.

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