proomt

Search

Search posts, papers, and topics

All posts

WebKit84 min readintermediate

WebKit Features for Safari 27.0

Read on webkit.org

Summary

Safari 27.0 adds a local MCP server for AI‑driven automation, a fully stylable `<select>` via `appearance: base-select` and new pseudo‑elements, the `<model>` element for embedding 3D assets, `sizes="auto"` for responsive images, a `shadowrootslotassignment` attribute for declarative shadow roots, and a large set of quality‑focused fixes (844 resolved issues).

  • Safari MCP exposes DOM, network, screenshots and console to external agents (Claude, Codex, etc.) without leaving the machine.
  • Customizable Select lets developers restyle native `<select>` controls with CSS only, preserving form semantics and accessibility.
  • The new `<model>` element works like `<img>`/`<video>` for USDZ/GLB assets and supports HDR tone‑mapping via `dynamic-range-limit`.
  • Responsive images can now use `sizes="auto"` to let the browser compute layout‑dependent sizes at runtime.

These additions reduce the need for heavy JavaScript workarounds (e.g., custom dropdowns, manual image‑size calculations) and open Safari to AI‑assisted testing and debugging, which can speed up front‑end development cycles. The quality‑fix focus (86 % of the release) also improves cross‑site compa…

5/10
frontendhtmlcssai agentweb components

Related reading

  1. Release Notes for Safari Technology Preview 252

    Safari Technology Preview 252 adds several WebKit platform updates, including new CSS features like named-feature() in @supports and unprefixed user-select, plus bug fixes across accessibility, animations, HTML, and JavaScript. The release also corrects worker termination, Promise.try behavior, and line‑clamp rendering, which can affect Safari‑targeted web apps.

    WebKitwebkit.org10 minrelease

  2. Release Notes for Safari Technology Preview 251

    Safari Technology Preview 251 introduces new CSS features like `@supports at-rule()` and `object-view-box`, alongside new JavaScript capabilities including `Iterator.prototype.includes()` and WebAssembly Memory64. This release also includes numerous bug fixes across HTML, CSS, and Canvas, and deprecates several non-standard CSS properties.

    WebKitwebkit.org19 minrelease

  3. Release Notes for Safari Technology Preview 250

    Safari Technology Preview 250 ships a batch of web‑platform updates, including new JavaScript resource‑management syntax, several CSS properties, streaming fetch bodies, and WebAssembly SIMD extensions. It also fixes a range of accessibility, rendering, and networking bugs.

    WebKitwebkit.org3 minrelease

  4. Fixing Top-Level Await in Safari

    Safari’s module loader was rewritten in C++ to follow the ECMAScript spec, fixing ordering and uninitialized‑export bugs that broke top‑level await. The new loader passes test262, WPT, and a custom fuzzer, and restores reliable module loading performance.

    WebKitwebkit.org7 min

  6. Firefox DevTools MCP 0.10.3 released

    Firefox DevTools MCP 0.10.3 is released, introducing a new `close_firefox_session` tool, full-page screenshot capability, and configurable download folders. This update also includes bug fixes and clarifies the usage of `restart_firefox` for controlling Firefox via WebDriver BiDi.

    Mozilla Automation Teammozilla.org1 minrelease