📅 August 2026 release notes
Newly available
The following features are newly available:
-
sibling-count() and sibling-index():
The
sibling-count()andsibling-index()CSS functions return integers that are useful to style elements based on their positions among siblings or on the number of siblings, for example as part of acalc()expression.
Widely available
The following features are now widely available:
-
Declarative shadow DOM:
The
shadowrootmodeattribute on<template>creates a shadow root without the use of JavaScript. It is a declarative alternative to theattachShadow()method.