Jekyll2026-05-24T01:11:00+00:00https://rixx.github.io/baseline-updates/feed/by_tag/selectors.xmlBaseline UpdatesUpdates to the Baseline collection. Including RSS feeds (both for all updates and individual tags).New in Low Baseline Support: :open2026-05-11T00:00:00+00:002026-05-11T00:00:00+00:00https://rixx.github.io/baseline-updates/2026/05/11/open-pseudocaniuse · mdn · spec

The :open CSS pseudo-class matches elements that have open states, like <details>, <dialog>, or <select>, based on their state.

Source features

  • css.selectors.open [mdn]
]]>New in High Baseline Support: :user-valid and :user-invalid2026-05-02T00:00:00+00:002026-05-02T00:00:00+00:00https://rixx.github.io/baseline-updates/2026/05/02/user-pseudoscaniuse · mdn · spec

The :user-valid and :user-invalid pseudo-classes match form controls that have been marked as valid or invalid based on their validation constraints.

Source features

  • css.selectors.user-invalid [mdn]
  • css.selectors.user-valid [mdn]
]]>New in Low Baseline Support: Active view transition2026-01-13T00:00:00+00:002026-01-13T00:00:00+00:00https://rixx.github.io/baseline-updates/2026/01/13/active-view-transitioncaniuse · mdn · spec

The :active-view-transition CSS pseudo-class matches the root element when a view transition is active. The :active-view-transition-type() CSS pseudo-class matches only when the active view transition was started with the specified type.

Source features

  • css.selectors.active-view-transition [mdn]
  • api.ViewTransition.types [mdn]
  • api.ViewTransitionTypeSet [mdn]
  • api.ViewTransitionTypeSet.@@iterator [mdn]
  • api.ViewTransitionTypeSet.add [mdn]
  • api.ViewTransitionTypeSet.clear [mdn]
  • api.ViewTransitionTypeSet.delete [mdn]
  • api.ViewTransitionTypeSet.entries [mdn]
  • api.ViewTransitionTypeSet.forEach [mdn]
  • api.ViewTransitionTypeSet.has [mdn]
  • api.ViewTransitionTypeSet.keys [mdn]
  • api.ViewTransitionTypeSet.size [mdn]
  • api.ViewTransitionTypeSet.values [mdn]
  • css.selectors.active-view-transition-type [mdn]
]]>New in High Baseline Support: :nth-child() of2025-11-09T00:00:00+00:002025-11-09T00:00:00+00:00https://rixx.github.io/baseline-updates/2025/11/09/nth-child-ofcaniuse · mdn · [spec]([‘https://drafts.csswg.org/selectors-4/#the-nth-child-pseudo’, ‘https://drafts.csswg.org/selectors-4/#the-nth-last-child-pseudo’])

The of syntax for the :nth-child() and :nth-last-child() CSS functional pseudo-classes match elements by the relative position of elements, counted from the first or last sibling matching a selector list.

Source features

  • css.selectors.nth-child.of_syntax [mdn]
  • css.selectors.nth-last-child.of_syntax [mdn]
]]>New in Low Baseline Support: ::details-content2025-09-16T00:00:00+00:002025-09-16T00:00:00+00:00https://rixx.github.io/baseline-updates/2025/09/16/details-contentcaniuse · mdn · spec

The ::details-content pseudo-element selects the expandable content of a <details> element, excluding the <summary>.

Source features

  • css.selectors.details-content [mdn]
]]>New in High Baseline Support: :modal2025-03-02T00:00:00+00:002025-03-02T00:00:00+00:00https://rixx.github.io/baseline-updates/2025/03/02/modalcaniuse · mdn · spec

The :modal pseudo-class selects elements that put other elements into a non-interactive state, such as a fullscreen element or a <dialog> element used with showModal().

Source features

  • css.selectors.modal [mdn]
]]>New in High Baseline Support: ::backdrop2024-09-14T00:00:00+00:002024-09-14T00:00:00+00:00https://rixx.github.io/baseline-updates/2024/09/14/backdropcaniuse · mdn · spec

The ::backdrop CSS pseudo-element is a box underneath an element in the top layer, such as a <dialog>. It can be used to create obscuring effects distinguishing a modal element from the elements underneath.

Source features

  • css.selectors.backdrop [mdn]
]]>New in High Baseline Support: :focus-visible2024-09-14T00:00:00+00:002024-09-14T00:00:00+00:00https://rixx.github.io/baseline-updates/2024/09/14/focus-visiblecaniuse · mdn · spec

The :focus-visible CSS pseudo-class selects elements that match the :focus pseudo-class and meets the browser’s criteria for visually emphasizing focused elements.

Source features

  • css.selectors.focus-visible [mdn]
]]>New in High Baseline Support: ::file-selector-button2023-10-26T00:00:00+00:002023-10-26T00:00:00+00:00https://rixx.github.io/baseline-updates/2023/10/26/file-selector-buttoncaniuse · mdn · spec

The ::file-selector-button CSS pseudo-element selects the button of a <input type="file"> element.

Source features

  • css.selectors.file-selector-button [mdn]
]]>New in High Baseline Support: :not2023-07-21T00:00:00+00:002023-07-21T00:00:00+00:00https://rixx.github.io/baseline-updates/2023/07/21/notcaniuse · mdn · spec

The :not() functional pseudo-class matches elements that do not match the selectors in its argument.

Source features

  • css.selectors.not [mdn]
  • css.selectors.not.selector_list [mdn]
]]>New in High Baseline Support: Shadow parts2023-01-28T00:00:00+00:002023-01-28T00:00:00+00:00https://rixx.github.io/baseline-updates/2023/01/28/shadow-partscaniuse · mdn · spec

The part and exportparts HTML attributes expose elements of a shadow DOM as named parts, which can be selected by the ::part() CSS pseudo-element for styling.

Source features

  • api.Element.part [mdn]
  • css.selectors.part [mdn]
  • html.global_attributes.exportparts [mdn]
  • html.global_attributes.part [mdn]
]]>New in High Baseline Support: Case-insensitive attribute selector2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/case-insensitive-attributescaniuse · mdn · spec

The i identifier in a CSS attribute selector matches attribute values case-insensitively in document languages like XML where attribute values are case-sensitive.

Source features

  • css.selectors.attribute.case_insensitive_modifier [mdn]
]]>New in High Baseline Support: :focus-within2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/focus-withincaniuse · mdn · spec

The :focus-within CSS pseudo-class matches an element if the element or any of its children are focused.

Source features

  • css.selectors.focus-within [mdn]
]]>New in High Baseline Support: Host2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/hostcaniuse · mdn · spec

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

Source features

  • css.selectors.host [mdn]
  • css.selectors.hostfunction [mdn]
]]>New in High Baseline Support: Link selectors2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/link-selectorscaniuse · mdn · spec

The :link CSS pseudo-class matches unvisited links, :visited matches visited links, and :any-link matches both.

Source features

  • css.selectors.visited [mdn]
  • css.selectors.link [mdn]
  • css.selectors.visited.privacy_measures [mdn]
  • css.selectors.any-link [mdn]
  • css.selectors.link.not_match_link [mdn]
  • css.selectors.visited.not_match_link [mdn]
  • css.selectors.any-link.not_match_link [mdn]
]]>New in High Baseline Support: :placeholder-shown2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/placeholder-showncaniuse · mdn · spec

The :placeholder-shown CSS pseudo-element selects <input> and <textarea> elements when no value is set and the element’s placeholder attribute is not empty. Not to be confused with ::placeholder, which selects the placeholder text itself.

Source features

  • css.selectors.placeholder-shown [mdn]
  • css.selectors.placeholder-shown.non_text_types [mdn]
]]>New in High Baseline Support: ::placeholder2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/placeholdercaniuse · mdn · spec

The ::placeholder CSS pseudo-element selects help text in <input> and <textarea> elements when no value is set.

Source features

  • css.selectors.placeholder [mdn]
]]>New in High Baseline Support: :scope (pseudo-class)2022-07-15T00:00:00+00:002022-07-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/07/15/scope-pseudocaniuse · mdn · spec

The :scope CSS pseudo-class matches the scoping root, for instance the element that querySelector() is called on, or the root of a DOM subtree specified with @scope.

Source features

  • css.selectors.scope [mdn]
  • css.selectors.scope.dom_api [mdn]
]]>New in Low Baseline Support: ::backdrop2022-03-14T00:00:00+00:002022-03-14T00:00:00+00:00https://rixx.github.io/baseline-updates/2022/03/14/backdropcaniuse · mdn · spec

The ::backdrop CSS pseudo-element is a box underneath an element in the top layer, such as a <dialog>. It can be used to create obscuring effects distinguishing a modal element from the elements underneath.

Source features

  • css.selectors.backdrop [mdn]
]]>New in Low Baseline Support: ::file-selector-button2021-04-26T00:00:00+00:002021-04-26T00:00:00+00:00https://rixx.github.io/baseline-updates/2021/04/26/file-selector-buttoncaniuse · mdn · spec

The ::file-selector-button CSS pseudo-element selects the button of a <input type="file"> element.

Source features

  • css.selectors.file-selector-button [mdn]
]]>New in Low Baseline Support: :not2021-01-21T00:00:00+00:002021-01-21T00:00:00+00:00https://rixx.github.io/baseline-updates/2021/01/21/notcaniuse · mdn · spec

The :not() functional pseudo-class matches elements that do not match the selectors in its argument.

Source features

  • css.selectors.not [mdn]
  • css.selectors.not.selector_list [mdn]
]]>New in Low Baseline Support: Shadow parts2020-07-28T00:00:00+00:002020-07-28T00:00:00+00:00https://rixx.github.io/baseline-updates/2020/07/28/shadow-partscaniuse · mdn · spec

The part and exportparts HTML attributes expose elements of a shadow DOM as named parts, which can be selected by the ::part() CSS pseudo-element for styling.

Source features

  • api.Element.part [mdn]
  • css.selectors.part [mdn]
  • html.global_attributes.exportparts [mdn]
  • html.global_attributes.part [mdn]
]]>New in Low Baseline Support: Case-insensitive attribute selector2020-01-15T00:00:00+00:002020-01-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2020/01/15/case-insensitive-attributescaniuse · mdn · spec

The i identifier in a CSS attribute selector matches attribute values case-insensitively in document languages like XML where attribute values are case-sensitive.

Source features

  • css.selectors.attribute.case_insensitive_modifier [mdn]
]]>New in Low Baseline Support: :focus-within2020-01-15T00:00:00+00:002020-01-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2020/01/15/focus-withincaniuse · mdn · spec

The :focus-within CSS pseudo-class matches an element if the element or any of its children are focused.

Source features

  • css.selectors.focus-within [mdn]
]]>New in Low Baseline Support: Host2020-01-15T00:00:00+00:002020-01-15T00:00:00+00:00https://rixx.github.io/baseline-updates/2020/01/15/hostcaniuse · mdn · spec

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

Source features

  • css.selectors.host [mdn]
  • css.selectors.hostfunction [mdn]
]]>