Intent to Prototype: baseline-source

[Ian Kilpatrick]

Contact emails

ikilp...@chromium.org

Explainer

None

Specification

https://drafts.csswg.org/css-inline-3/#baseline-source

Summary

The "baseline-source" properties allows web developers to specify if an inline-level box should use the "first" or "last" baseline for alignment within an linebox. Today the default behaviour is confusing for web developers. Consider: test <div style="display: inline-block;">line1<br>line2</div> test <div style="display: inline-flex;">line1<br>line2</div> The "inline-block" will align to the last baseline, and the "inline-flex" will align to the first baseline. "baseline-source: auto" is the existing (confusing) behaviour. Web developers can specify "baseline-source: first" or "baseline-source: last" to directly determine how they want these boxes to align within a line-box.

Blink component

Blink>Layout>Inline

Motivation

From changes to last/first baseline features we've received requests from web developers to have more precise control over which baseline to use for alignment within a line-box.

Initial public proposal

TAG review

TAG review status

Not applicable

Risks

Interoperability and Compatibility

Gecko: No signal

WebKit: No signal

Web developers: Positive - see motivation above.

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?

Debuggability

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

Not yet we'll be adding a full suite of tests in css/css-inline/baseline-source

Flag name

CSSBaselineSource

Requires code in //chrome?

False

Tracking bug

https://bugs.chromium.org/p/chromium/issues/detail?id=1399711

Estimated milestones

No milestones specified

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/5730575560736768

This intent message was generated by Chrome Platform Status.