Apple Details Safari 27 Update Featuring MCP Support and CSS Scroll Anchoring
Apple's WebKit team announced Safari 27, introducing native support for the Model Context Protocol (MCP) server, CSS scroll anchoring, and 844 bug fixes. The update provides enhanced browser debugging capabilities for AI assistants and eliminates content jumping while users read dynamic webpages. Integrating MCP allows AI tools like Claude Code and Codex to directly control the browser and debug web applications, streamlining developer workflows. Meanwhile, implementing standard CSS scroll anchoring greatly improves user experience by stabilizing the viewport when ads or dynamic content load asynchronously. Through MCP support, AI tools can inspect DOM structures, monitor network requests, capture screenshots, and read console logs. Scroll anchoring is governed by the `overflow-anchor` CSS property (defaulting to `auto`), maintaining position stability unless developers explicitly disable it using `overflow-anchor: none`.
## BACKGROUND
Model Context Protocol (MCP) is an open standard created by Anthropic to standardize how artificial intelligence systems connect and interact with external applications and execution environments. CSS scroll anchoring is a web standard designed to prevent page content from unexpectedly shifting when dynamic elements load above the user's visible region.