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Window Management

W3C TPAC 2024 Update (Sept 2024) - Second Screen WG

Brad Triebwasser -btriebw@google.com

Mike Wasserman - msw@google.com

Spec: github.com/w3c/window-management

Demos: github.com/michaelwasserman/window-placement-demo

github.com/michaelwasserman/iwa-windowing-example

Prior: Sept 2023 Slides | Sep 2022 Slides | May 2022 vF2F | Oct 2021 Slides

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Present Landscape

Window Management capabilities on the web are stronger today than ever before!

Screen details, cross-screen window placement, and fullscreen
NEW! MDN API reference d ocumentation
Fullscreen Capability Delegation, Fullscreen Companion Windows
Gesture requirement configuration for Popups
Gesture requirement configuration for Fullscreen (NEW! IWA+Enterprise)

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Present Landscape

New! Google Slides multi-monitor presentations

“Multi-monitor support is absolutely vital with presentation software” - Android Police

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HTML Fullscreen Without A Gesture

Explainer, ChromeStatus (Chrome 127+), Demo

Motivation: Gesture requirements preclude advanced fullscreen capabilities

Goal: Enable new fullscreen use cases:

Open new fullscreen popups (e.g. multi-screen fullscreen)
Extend fullscreen onto newly connected displays
Enter fullscreen after activation consumption or expiry (long-tail)

Proposal: HTML Fullscreen gesture req. configurations (spec Issue + PR) + permission query:

navigator.permissions.query({name: 'fullscreen', allowWithoutGesture: true});

Supersedes Fullscreen Popup Windows and Many Windows Many Screens

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Future Landscape

User and developer feedback informs future investment:

Extending APIs: screen IDs, refresh rates, HDR/WCG
Platform support: Android, Wayland best effort and feature detection
Implementation fixes: fullscreen promises, window bounds oddities
API modernization: window.setBounds(), window.open(), etc.
New capabilities: Additional Windowing Controls, window.onmove, Borderless

Hopeful other UAs will someday also support modern Window Management functionality

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Virtual Display Testing

Chromium test framework support for managing virtual displays at the OS level

Implementation complete on all desktop platforms (Windows, Mac, Linux (X11), ChromeOS).

All multi-screen tests migrated to new utility.

Next Steps:

Advocate for Apple to officially support the private CoreGraphics APIs.
Develop a wpt driver to support testing multi-screen APIs in web platform tests.

We have made progress on our virtual display testing efforts. We have extended our framework initially developed on Mac to Windows(driver), linux (X11) and ChromeOS. We now have a single utility that can seamlessly manage virtual displays across all desktop platforms. This unlocks the ability to automatically test multi-screen chrome features in any environment (e.g. single display, or headless environments (I.e. CI pipelines)). We have migrated all integration tests to use this.

Next Steps:

Our solution relies on private APIs on Mac OS. We have filed a request to Apple to officially support these apis as it would improve reliability and help all developers test their multi-screen software.

Develop a WPT driver so that we can add web platform tests for multi-screen features. Hopefully encourage other vendors to implement window-management and support the web platform tests.

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Virtual Displays: Cast Extended Desktop

Prototyped an alternative way to cast from the browser.

Seamlessly create a virtual display and cast it to a nearby Chromecast device.

Use cases:

Using a Chromecast supported tablet as a secondary monitor (Similar to Sidecar)
Conducting a presentation: wirelessly cast slides to screen and maintain speaker notes on your laptop.

LIVE DEMO

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Nearby Screens Demo

Pre-recorded videos

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Thanks!