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Web Platform Baseline Status Breakdown Total Features: 1191
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Showing 10 of 10 features

Limited Availability

10 features
• In Progress / Not Yet Baseline

The ::selection CSS pseudo-element selects text a user has highlighted.

Chrome 1
Firefox 62
Safari 1.1
Edge 12
Status: Incomplete cross-engine support

The ::spelling-error and ::grammar-error CSS pseudo-elements match text that is highlighted as misspelled and grammatically incorrect, respectively.

Chrome 121
Firefox
Safari 17.4
Edge 121
Status: Incomplete cross-engine support

The :has-slotted CSS pseudo-class matches <slot> elements where the fallback content is not shown. The pseudo-class matches any slotted content, including white space, text nodes, or elements.

Chrome
Firefox 136
Safari
Edge
Status: Incomplete cross-engine support

The :host-context() CSS pseudo-class selects the containing element of the shadow tree in which it is used if that element or an ancestor matches the provided selector.

Chrome 54
Firefox
Safari
Edge 79
Status: Incomplete cross-engine support

The :target-within CSS pseudo-class matches the element with an ID matching the URL fragment and its ancestors.

Chrome
Firefox
Safari
Edge
Status: Incomplete cross-engine support

The s identifier in a CSS attribute selector matches attribute values case-sensitively in document languages like HTML where attribute values are case-insensitive.

Chrome
Firefox 66
Safari
Edge
Status: Incomplete cross-engine support

The :heading and :heading() CSS pseudo-classes match headings of varying levels. The :heading pseudo-class matches any heading (<h1> through <h6>). The :heading() selector matches any of the given levels. For example, :heading(1, 2) matches headings level 1 and 2.

Chrome
Firefox
Safari
Edge
Status: Incomplete cross-engine support

The :first, :left, and :right pseudo-classes select pages based on their position in sequence after pagination.

Chrome 18
Firefox
Safari 6
Edge 12
Status: Incomplete cross-engine support

The :past and :future CSS pseudo-classes match prior or upcoming text track cues during media playback.

Chrome 23
Firefox
Safari 7
Edge 79
Status: Incomplete cross-engine support

The text-decoration CSS property in a ::selection rule sets the underline and other text decoration styles on the text a user has highlighted.

Chrome 105
Firefox
Safari
Edge 105
Status: Incomplete cross-engine support