Intent to Ship: Scoped Custom Element Registry

[Chromestatus]

Contact emails

mason...@google.com, jayso...@microsoft.com, leo...@microsoft.com

Explainer

https://github.com/WICG/webcomponents/blob/gh-pages/proposals/Scoped-Custom-Element-Registries.md
https://github.com/whatwg/html/issues/10854

Specification

https://html.spec.whatwg.org/multipage/custom-elements.html#customelementregistry

Summary

This feature allows for multiple custom element definitions for a single tag name to exist within a page to prevent custom element name conflicts when a web app uses libraries from multiple sources. This is achieved by allowing user code to create multiple custom element registries and associate them with tree scopes and elements that function as scoping object for custom element creation/definition/upgrade.

Blink component

Blink>HTML>CustomElements

Web Feature ID

scoped-custom-element-registries

TAG review

https://github.com/w3ctag/design-reviews/issues/1070

TAG review status

Issues addressed

Risks

Interoperability and Compatibility

None

Gecko: Positive (https://github.com/mozilla/standards-positions/issues/424)

WebKit: Shipped/Shipping (https://developer.apple.com/documentation/safari-release-notes/safari-26-release-notes)

Web developers: Positive Scoped custom element registry has been a long-awaited feature from the Web Components Community Group, and the current polyfill that didn't solve the entire problem has 24k+ downloads per week.

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?

None

Debuggability

None

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

Yes

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

Yes
https://wpt.fyi/results/custom-elements/registries?label=master&label=experimental&aligned

Flag name on about://flags

None

Finch feature name

ScopedCustomElementRegistry

Rollout plan

Will ship enabled for all users

Requires code in //chrome?

False

Tracking bug

https://issues.chromium.org/issues/40826514

Estimated milestones

Shipping on desktop	143
Shipping on Android	143
Shipping on WebView	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/5090435261792256?gate=6499099686207488

Links to previous Intent discussions

Intent to Prototype: https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAFqEGhaAi0t1ffJoE8Du9bB2Wwxt6CewJjxz2Y_m9qWuoAa-Ug%40mail.gmail.com

This intent message was generated by Chrome Platform Status.