WebKit features for Safari 27.1 and 27.2

2026-10-28

Safari Web Inspector Timelines for web-standards.dev with Layout & Rendering, JavaScript & Events, and CPU graphs, the Safari icon, and the headline “WebKit Features for Safari 27.1–27.2”.

Jen Simmons covers two releases. Safari 27.1 brings Device Posture and Viewport Segments APIs for iPhone Duo behind flags, and two-page PDFs when folded. Safari 27.2 adds ::field-content for customizable <select> and renames flow-tolerance to fit-tolerance in Grid Lanes. With align-self: safe center, absolutely positioned boxes stay inside their container. Plus 20 bug fixes.

Tags browser safari

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