Intent to Ship: FontFace width attribute and font-width descriptor

[Chromestatus]

Contact emails

michael....@gmail.com

Specification

https://drafts.csswg.org/css-fonts-4/#font-width-prop

Summary

Exposes the width attribute on FontFace and the @font-face font-width descriptor as aliases for stretch and font-stretch. Aligns Chromium with the updated CSS Font Loading and CSS Fonts 4 specifications. Developers can now inspect or initialize font face widths using FontFace.width and CSS font-width interchangeably with stretch and font-stretch.

Blink component

Blink>CSS

Web Feature ID

font-width

Motivation

CSS Font Loading and CSS Fonts 4 define width as the primary FontFace descriptor attribute and @font-face descriptor, while retaining stretch as a legacy alias. Chromium previously ignored the width constructor member and font-width descriptor, causing Web Platform Tests to fail. Exposing width aligns Chromium with the updated specification.

Initial public proposal

No information provided

TAG review

Not needed - Small spec-alignment bug fix.

TAG review status

Not applicable

Goals for experimentation

None

Risks

Interoperability and Compatibility

Low risk. Fixes failing Web Platform Tests and aligns Chromium with the updated CSS Font Loading and CSS Fonts 4 specifications.

Gecko: Shipped/Shipping (https://wpt.fyi/results/css/css-font-loading/font-face-width-descriptor-aliasing.html) Firefox passes the test.

WebKit: No signal

Web developers: No signals

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. It is strictly additive aliasing for existing stretch functionality.

Debuggability

No special DevTools debugging support required. Standard CSS descriptor inspection applies.

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

Yes
Supported in Blink CSS core.

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

Yes
https://wpt.fyi/results/css/css-font-loading/font-face-width-descriptor-aliasing.html

Flag name on about://flags

No information provided

Finch feature name

No information provided

Non-finch justification

Waterfall rollout without Finch flag.

Rollout plan

Will ship enabled for all users

Requires code in //chrome?

False

Tracking bug

https://issues.chromium.org/issues/543938492

Measurement

None

Availability expectation

Feature is available on Web Platform Baseline within 12 months of launch in Chrome.

Adoption expectation

Feature is considered a best practice for configuring font face width descriptors within 12 months of reaching Web Platform baseline.

Adoption plan

Web Platform Tests (WPT) have been added to ensure cross-browser interoperability. MDN documentation will be updated to reflect FontFace.width as the standard descriptor.

Non-OSS dependencies

Does the feature depend on any code or APIs outside the Chromium open source repository and its open-source dependencies to function?

No

Estimated milestones

Shipping on desktop	153
Shipping on Android	153
Shipping on WebView	153

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/5145402365050880?gate=5525688097570816

This intent message was generated by Chrome Platform Status.