CSS Custom Highlight Universal Selector `::highlight(*)`

[DevSDK]

Specification

Spec work in progress:
Spec issue: w3c/csswg-drafts#9091
Spec PR: w3c/csswg-drafts#14301

Description

Introduces a universal selector for custom highlights, ::highlight(*), which matches the highlight pseudo-elements of all custom highlights regardless of their name.

The * argument contributes zero specificity, so its declarations act as a base style that rules naming a specific highlight override through the cascade.

Documentation

N/A

Browser support

• https://chromestatus.com/feature/5174965228929024

[ddbeck]

Thanks for filing this issue, @DevSDK. To mint the feature entry, I'm taking some notes below. You're not required to review this comment, but your input is very welcome, particularly on the name and description.

Name and ID

The ID here is easy. Since this builds on the existing Custom highlights (source, dist) feature entry, the ID should probably extend highlight. I'm recommending the ID highlight-unviersal-selector.

The name is probably the literal code that invokes the feature: ::highlight(*).

Description

Adapting the text provided to our style guide, I'm proposing the following description:

The ::highlight(*) CSS pseudo-element selects all custom highlight pseudo-elements regardless of their name. The * argument adds zero specificity, so you can use it to create a base style for custom highlights that you can override by selecting a highlight by name.

Compat keys

There's no data for this yet (there won't be until a browser has an implementation in a beta release or better). But I expect this to appear as one key, css.selectors.highlight.universal (or close to it).

Background

I've edited the issue description to add links to the Chrome Status entry and the spec issue related to your spec PR. I didn't find any standards position requests related to this.

It looks like this feature request is still pretty early—as far as I can tell no implementation work has happened yet—so I've labeled this as an early feature.

[DevSDK]

Name LGTM. So is it fine to put the name highlight-unviersal-selector to the Chrome feature entry's Web Feature ID section?

[ddbeck]

It's probably safe to do it, though it'll be a little bit before I get to minting this one officially (unfortunately, there's a bit of a backlog on already-shipping features to work on ahead of this one—sorry!).