Bug: Claude for Chrome extension installed and enabled, but never registers as a connected browser in a Cowork cloud session

Bug: Claude for Chrome extension installed and enabled, but never registers as a connected browser in a Cowork cloud session

Labels: bug, claude-in-chrome

Summary

In a Cowork (remote/cloud) session, all mcp__claude-in-chrome__* tools report that no browser is connected, even though the Claude for Chrome extension is installed and enabled in the local Chrome. The extension never appears in list_connected_browsers, so no browser automation is possible. The separate remote-devices desktop bridge to the same Mac works normally, which suggests the desktop↔cloud link is healthy and the failure is specific to Chrome extension pairing.

Environment

• Session type: Cowork mode, remote/cloud container (Claude Agent SDK)
• Configured model: claude-opus-5
• Desktop app version: 1.34493.1 (Electron 42.9.2, Node 24.18.1)
• OS: macOS, arm64 (darwin)
• Device name: macbook-pro-4-local
• Chrome: Claude for Chrome extension present and toggled ON (verified at chrome://extensions — listed as "Claude / Claude in Chrome")
• Other extension installed: 1Password
• Session account: arvind@factsoftware.com

Steps to reproduce

1. Start a Cowork cloud session on the desktop app.
2. Confirm the Claude for Chrome extension is installed and enabled at chrome://extensions.
3. Ask Claude to perform any browser action, or call the tools directly:

• mcp__claude-in-chrome__list_connected_browsers
• mcp__claude-in-chrome__tabs_context_mcp with createIfEmpty: true
• mcp__claude-in-chrome__switch_browser

Expected behaviour

list_connected_browsers returns at least one entry for the local Chrome, and tabs_context_mcp creates or returns a tab group so browser automation can proceed.

Actual behaviour

• list_connected_browsers → [] (empty array, every time)
• tabs_context_mcp {createIfEmpty: true} → Browser extension is not connected. Please ensure the Claude browser extension is installed and running (https://claude.ai/chrome), and that you are logged into claude.ai with the same account as Claude Code...
• switch_browser → No other browsers available to switch to. Open Chrome with the Claude extension in another browser to switch.

Note that switch_browser is documented as broadcasting a connect prompt to every Chrome with the extension installed. It never surfaced a prompt in the local Chrome, so the broadcast does not appear to reach an installed-but-unpaired extension.

What was already tried

• 6 separate checks spread over roughly 10 minutes
• 2 full Chrome quit-and-relaunch cycles (not just window close)
• Verified extension is installed AND enabled via chrome://extensions
• switch_browser broadcast (no prompt appeared in Chrome)

Contrast: the device bridge works

In the same session, mcp__remote-devices__get_device_info succeeds and returns full device details (platform, app version, home directories). So the desktop app is reachable from the cloud container; only the Chrome extension pairing fails.

Impact

Browser automation is completely unavailable in the session with no actionable diagnostic. The error message points at three possible causes (not installed / not running / account mismatch) without indicating which applies, so there is no way to tell an account mismatch apart from a failed handshake.

Suggested improvements

1. Have list_connected_browsers or the error message distinguish "no extension detected at all" from "extension detected but signed into a different account" — and name the account the session expects.
2. Surface the extension's signed-in account somewhere queryable, so a mismatch is diagnosable without guesswork.
3. Make switch_browser's broadcast reach installed-but-unpaired extensions, or state explicitly that it only reaches already-authenticated ones.