Web-Facing Change PSA: Clone into all descendant selectedcontent elements

[Joey Arhar]

Contact emails

jar...@chromium.org

Specification

https://github.com/whatwg/html/pull/12263

Summary

Multiple small changes are being made to edge cases of the selectedcontent element:

- When multiple selectedcontent elements are put in a select element at the same time, all of them will be kept up to date instead of only the first one in DOM order.
- Updating the selectedcontent element is deferred when it would run during insertion, removal, or moving steps in order to fix security issues. The update is deferred by using post-insertion steps or microtasks. This is a PSA instead of an intent to ship because this only changes invalid cases or edge cases, and the usage of customizable select is still quite low (0.02%).

Blink component

Blink>Forms>Select

Web Feature ID

No information provided

Risks

Interoperability and Compatibility

The risk is low for the reasons I mentioned in the summary.

Gecko: No signal (https://github.com/whatwg/html/pull/12263)

WebKit: No signal (https://github.com/whatwg/html/pull/12263)

Feedback from Apple is the primary motivation for changing the selectedcontent element in this way, so I am confident that WebKit will follow through with this change.

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?

No

Debuggability

No information provided

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

Tracking bug

https://issues.chromium.org/issues/458113204

Estimated milestones

Shipping on desktop	150
Shipping on Android	150
Shipping on WebView	150

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/5863985044914176

This intent message was generated by Chrome Platform Status.