Intent to Implement and Ship: Fullscreen Capability Delegation

Mustaq Ahmed

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Apr 21, 2022, 11:06:38 AM4/21/22

to blink-dev, Michael Wasserman

Summary

This feature is based on the general delegation mechanism (https://chromestatus.com/feature/5708770829139968) shipped on M100.

Fullscreen Capability Delegation allows a Window to transfer the ability to call requestFullscreen() to another Window it trusts after relinquishing the transient user activation at the sender Window.

Blink component

Blink>Fullscreen

TAG review

Covered by the review for the general delegation mechanism: https://github.com/w3ctag/design-reviews/issues/655

TAG review status

Covered by the approval for the general delegation mechanism: https://github.com/WICG/capability-delegation/pull/23

Risks

Interoperability and Compatibility risks remain unchanged from the general delegation mechanism; see that intent here: https://groups.google.com/a/chromium.org/g/blink-dev/c/PHT_2X7oRBE/m/gR9UiZxBAQAJ

External signals

Gecko: Positive (https://github.com/mozilla/standards-positions/issues/565, also see: https://github.com/WICG/capability-delegation/issues/10)

WebKit: No signal

Web developers: Positive (https://crbug.com/931966#c5)

Debuggability

This remains unchanged from the general intent: https://groups.google.com/a/chromium.org/g/blink-dev/c/PHT_2X7oRBE/m/gR9UiZxBAQAJ

Ongoing technical constraints

None.

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

Yes

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

Not yet

Flag name

--enable-blink-features=CapabilityDelegationFullscreenRequest

Requires code in //chrome?

Yes, work in progress

Tracking bug

https://crbug.com/1293083

Estimated milestone

103

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/6441688242323456

Links to previous Intent discussions

Intents for the general delegation mechanism:

I2P: https://groups.google.com/a/chromium.org/g/blink-dev/c/9CeLYndESPE/m/AhEttheMBQAJ
I2E (with Payment Request): https://groups.google.com/a/chromium.org/g/blink-dev/c/i6pAWsjU7zg/m/UK0lGnKuAAAJ

I2S (with Payment Request): https://groups.google.com/a/chromium.org/g/blink-dev/c/PHT_2X7oRBE/m/gR9UiZxBAQAJ

Mike Taylor

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Apr 25, 2022, 3:29:29 PM4/25/22

to Mustaq Ahmed, Michael Wasserman, blink-dev

Hi Mustaq,

On 4/21/22 11:05 AM, Mustaq Ahmed wrote:

Contact emails

mus...@chromium.org, m...@chromium.org

Explainer

https://github.com/WICG/capability-delegation

Specification

https://wicg.github.io/capability-delegation/spec.html

(Work in progress for fullscreen algorithm change: https://github.com/WICG/capability-delegation/pull/28)

Design doc

https://docs.google.com/document/d/1ax54Lf2W3_TovVOj35duKTbcOlXe-nJ-KQdWiy1Ye0c

Summary

This feature is based on the general delegation mechanism (https://chromestatus.com/feature/5708770829139968) shipped on M100.

Fullscreen Capability Delegation allows a Window to transfer the ability to call requestFullscreen() to another Window it trusts after relinquishing the transient user activation at the sender Window.

Does this only work for standard requestFullscreen, or will it work for webkitRequestFullscreen as well?

Blink component

Blink>Fullscreen

TAG review

Covered by the review for the general delegation mechanism: https://github.com/w3ctag/design-reviews/issues/655

TAG review status

Covered by the approval for the general delegation mechanism: https://github.com/WICG/capability-delegation/pull/23

Risks

Interoperability and Compatibility risks remain unchanged from the general delegation mechanism; see that intent here: https://groups.google.com/a/chromium.org/g/blink-dev/c/PHT_2X7oRBE/m/gR9UiZxBAQAJ

External signals

Gecko: Positive (https://github.com/mozilla/standards-positions/issues/565, also see: https://github.com/WICG/capability-delegation/issues/10)

I don't think these quite count as official Positive signals (but yes, the comments from Anne are promising!). Can we ping the standards-position issue and ask for one?

WebKit: No signal

Have we asked? I looked at the Payment Request, and it seems like we didn't, but maybe I'm looking in the wrong spot. If not, can we?

Web developers: Positive (https://crbug.com/931966#c5)

Debuggability

This remains unchanged from the general intent: https://groups.google.com/a/chromium.org/g/blink-dev/c/PHT_2X7oRBE/m/gR9UiZxBAQAJ

Ongoing technical constraints

None.

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

Yes

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

Not yet

Is there something missing to test this (or capability detection in general), or is it just that you haven't written the WPTs yet?

Flag name

--enable-blink-features=CapabilityDelegationFullscreenRequest

Requires code in //chrome?

Yes, work in progress

Tracking bug

https://crbug.com/1293083

Estimated milestone

103

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/6441688242323456

Links to previous Intent discussions

Intents for the general delegation mechanism:

I2P: https://groups.google.com/a/chromium.org/g/blink-dev/c/9CeLYndESPE/m/AhEttheMBQAJ

I2E (with Payment Request): https://groups.google.com/a/chromium.org/g/blink-dev/c/i6pAWsjU7zg/m/UK0lGnKuAAAJ

I2S (with Payment Request): https://groups.google.com/a/chromium.org/g/blink-dev/c/PHT_2X7oRBE/m/gR9UiZxBAQAJ

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Ajay Rahatekar

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May 8, 2022, 11:07:02 PM5/8/22

to blink-dev, mike...@chromium.org, Mike Wasserman, blink-dev, mus...@chromium.org

+Ajay Rahatekar

Mustaq Ahmed

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May 9, 2022, 5:05:15 PM5/9/22

to Mike Taylor, Ajay Rahatekar, blink-dev, Mike Wasserman

Hi Mike:

Sorry for the delay due to vacation etc! Below are my answers to your queries. Note that we are still asking for M103, so we will be prompt now :)

> Does this only work for standard requestFullscreen, or will it work for webkitRequestFullscreen as well?

This covers all forms: we are proposing changes in the core algorithm for request-fullscreen, regardless of the JS interface used to call it.

>> Gecko: Positive (https://github.com/mozilla/standards-positions/issues/565, also see: https://github.com/WICG/capability-delegation/issues/10)

> I don't think these quite count as official Positive signals (but yes, the comments from Anne are promising!). Can we ping the standards-position issue and ask for one?

See the recent comments in the issue asking for Gecko's position, thanks.

https://github.com/mozilla/standards-positions/issues/565

>> WebKit: No signal
> Have we asked? I looked at the Payment Request, and it seems like we didn't, but maybe I'm looking in the wrong spot. If not, can we?

I missed this with the intent for payment, sorry! Filed a single request to cover both payment and fullscreen capabilities:

https://lists.webkit.org/pipermail/webkit-dev/2022-May/032221.html

>> Is this feature fully tested by web-platform-tests?
>> Not yet
> Is there something missing to test this (or capability detection in general), or is it just that you haven't written the WPTs yet?

We hadn't written a WPT at that time. We have one under review now:

https://github.com/web-platform-tests/wpt/pull/34004

Mustaq

Mike Taylor

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May 9, 2022, 6:37:23 PM5/9/22

to Mustaq Ahmed, Ajay Rahatekar, blink-dev, Mike Wasserman

Hey Mustaq - welcome back. :)

Thanks for the answers, and for requesting the missing WebKit position.

LGTM1

Mike West

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May 11, 2022, 1:38:01 AM5/11/22

to Mike Taylor, Mustaq Ahmed, Ajay Rahatekar, blink-dev, Mike Wasserman

LGTM2.

-mike

To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/f4a6af83-56b0-f390-10d0-be7cd9d12780%40chromium.org.

Daniel Bratell

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May 11, 2022, 2:30:15 AM5/11/22

to Mike West, Mike Taylor, Mustaq Ahmed, Ajay Rahatekar, blink-dev, Mike Wasserman

LGTM3

To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAKXHy%3DeSAWS83NVoHJUhn2pAViA8pMogmcx5CcBWHvL2BHeY6A%40mail.gmail.com.

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