WebKit called the release notes for Safari 27.0 the longest ever: the feature count rose from 58 to 80 since the first June beta, and the quality effort reached 844 fixes after starting at 525 at WWDC. Four changes matter for everyday web work.
What to actually read
- Safari MCP gives coding agents access to the DOM, network requests, screenshots, and console output. It runs locally and makes no network calls of its own.
- Scroll anchoring keeps your reading position stable when content injects above you, with no code on your side.
- The model element brings real 3D into iOS, iPadOS, and macOS pages, and on visionOS sites can ship immersive environments with one API call.
- A complete rewrite of the ES module loader fixes the module execution order issues that made top-level await a Safari pain point.
CSS picks worth noting
The stretch keyword replaces the -webkit-fill-available hack. The sizes=auto keyword lets a lazy image size itself from the real layout. Anchor positioning gained transform-aware tracking, and color-mix accepts more than two colors now. Small API, big cleanup, gacor.
Our coverage of the fixes that ride along: Safari 27.1 shipped beside iPhone Duo, Safari 27.2 refined select a month later, and the top-level await story has its own writeup.