WebKit features in Safari 27

2026-09-16

Safari Web Inspector Timelines view with Layout & Rendering, JavaScript & Events, CPU, and Memory graphs, overlaid by the Safari icon and the headline “WebKit Features for Safari 27”.

Customizable <select>, scroll anchoring, WebAssembly JSPI, ariaNotify(), the :heading pseudo-class, revert-rule, stretch sizing, sizes="auto", import defer, subpixel inline layout, and the service worker static routing API — a total of 83 new features and 844 fixes, plus major updates in WebRTC, MathML, spatial web, web extensions, and developer tools.

developer.apple.com/documentation/safari-release-notes/safari-27-release-notes

Tags browser safari

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