css

WebKit says Safari 27.3 beta's Adaptive Dark Mode darkens light pages for users who enable it but leaves alone pages that declare dark-mode support; the opt-out keyword it names is unsupported in beta 1.

Firefox 159, released October 27, 2026, enables scroll-driven animations by default and adds scoped custom element registries, which web.dev lists as Baseline Newly available; legacy masonry syntax is removed.

Tailwind CSS v4.3.4 adds a Turbopack loader package for Next.js and lists fixes for watch mode, the Vite plugin, WASM fallback and standalone macOS binary signing.

The minimalist Pico CSS framework says v2.1.1 is its final release and its repositories are archived, while its MIT license allows forks that use a different name.

Mozilla's Firefox 157 brings the Nova visual refresh, a returning compact mode, hardware AV1 decoding in WebRTC, and new CSS support for at-rule() and overscroll-behavior: chain.

Chrome 154 reached stable on September 22 with a frame-sizing property for iframes that size to their content, links and tabs modes for scroll markers, and text-decoration-inset.