[BUG] Claude in Chrome: MCP tool calls now steal tab focus (regression ~26 Mar 2026)

Description

As of approximately 26 March 2026, every MCP tool call that touches a tab in the Claude in Chrome group (screenshot, navigate, read_page, javascript_tool, etc.) now brings that tab to the foreground and steals focus from whichever application was active.

Previously, tool calls operated on tabs silently without changing focus. This is a regression -- the behaviour changed without any action on my end.

Impact

When Claude Code is running a multi-step task that interacts with browser tabs (e.g. taking screenshots, reading page content, checking console messages), Chrome aggressively steals focus on every single tool call. This makes it impossible to work in another application (terminal, editor, etc.) while Claude is operating on browser tabs.

Expected behaviour

Tool calls should operate on tabs without bringing Chrome to the foreground or switching the active tab, matching the previous behaviour.

Environment

• macOS
• Chrome (latest stable)
• Claude in Chrome extension (latest from Chrome Web Store)
• Claude Code CLI

Related

• #31119 requests an active parameter for explicit control -- but this issue is about a regression in the default behaviour, not a missing feature.