[BUG] Claude Desktop Cowork: "Check your Claude in Chrome account" error persists despite correct account, working native messaging, and active socket connection

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Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report (please file separate reports for different bugs)
• I am using the latest version of Claude Code

What's Wrong?

Claude Desktop's Cowork mode consistently fails to connect to Chrome with the error "Check your Claude in Chrome account", even though:

1. The Chrome extension and Claude Desktop are signed in with the same account
2. The native messaging host is running correctly and creating Unix sockets
3. MCP clients are successfully connecting to the socket
4. Claude Code CLI (claude --chrome) connects to the same Chrome extension without any issues

This is NOT a race condition (Chrome is already fully loaded), and dismissing the dialog + retrying does NOT resolve it.

Environment

• macOS Darwin 24.6.0 (Apple Silicon)
• Claude Desktop: latest (as of 2026-03-20)
• Claude Code CLI: 2.1.80
• Chrome extension: v1.0.63 (ID: fcoeoabgfenejglbffodgkkbkcdhcgfn), installed in Default profile
• Chrome has 3 profiles; extension is in Default

What Should Happen?

Cowork should connect to Chrome successfully, just like Claude Code CLI does.

Diagnostic Evidence

1. Claude Code CLI works fine

With the tengu_copper_bridge=false workaround (see #24593), Claude Code CLI connects to Chrome without issues:

$ CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1 claude --chrome
# tabs_context_mcp returns available tabs successfully

2. Native messaging host is healthy

~/Library/Logs/Claude/chrome-native-host.log shows clean socket creation and successful MCP client connections — no errors:

[2026-03-20 20:25:52] Chrome native host starting (version 0.1.0)
[2026-03-20 20:25:52] Socket created successfully at: /tmp/claude-mcp-browser-bridge-rudolph/84818.sock
[2026-03-20 20:25:52] Entering main message loop
[2026-03-20 20:25:52] Socket server listening for connections
[2026-03-20 20:27:18] Accepted new MCP connection (client 1). Total clients: 1
[2026-03-20 20:27:18] MCP client 1 connected

3. Socket is active and connected

$ ls -la /tmp/claude-mcp-browser-bridge-rudolph/
srw-------  1 rudolph  wheel  0 Mar 20 20:25 84818.sock

$ lsof -U | grep claude-mcp
chrome-na 84818 rudolph  10u  unix  ...  /tmp/claude-mcp-browser-bridge-rudolph/84818.sock

The native host process (/Applications/Claude.app/Contents/Helpers/chrome-native-host) is running and connected to the Chrome extension.

4. Desktop config is correct

// ~/Library/Application Support/Claude/claude_desktop_config.json
{
  "preferences": {
    "chromeExtensionEnabled": true
  }
}

5. Native messaging manifest is correct

// ~/Library/Application Support/Google/Chrome/NativeMessagingHosts/com.anthropic.claude_browser_extension.json
{
  "name": "com.anthropic.claude_browser_extension",
  "path": "/Applications/Claude.app/Contents/Helpers/chrome-native-host",
  "type": "stdio",
  "allowed_origins": [
    "chrome-extension://fcoeoabgfenejglbffodgkkbkcdhcgfn/"
  ]
}

What I've already tried (all failed)

• Restarting Chrome
• Restarting Claude Desktop (full Cmd+Q)
• Logging out and back in to Claude Desktop (to refresh OAuth token)
• Confirming Chrome is the default browser (it is)
• Reloading the Chrome extension
• Setting tengu_copper_bridge=false in ~/.claude.json
• Setting CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1 via launchctl setenv for GUI apps
• Dismissing the error dialog and retrying multiple times

Root Cause Analysis

The local connection path (native messaging + Unix socket) works perfectly — both Claude Code CLI and the native host logs confirm this.

The issue is that Claude Desktop performs an account verification check via the cloud WebSocket bridge (wss://bridge.claudeusercontent.com) before allowing Cowork to use Chrome tools. This bridge verification fails (likely the same OAuth token validation bug reported in #24593), and Desktop shows the error dialog without falling back to the working local connection.

Unlike Claude Code CLI, Claude Desktop does not respect CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1 or tengu_copper_bridge=false, so there is no user-side workaround for Cowork.

Suggested Fix

1. Apply the same bridge bypass that works for Claude Code CLI to Claude Desktop
2. Or: if the local socket connection is healthy, skip/defer the bridge account verification and let the connection proceed
3. Or: fix the bridge's OAuth token validation (root cause of [BUG] Claude-in-Chrome: Browser extension persistently fails to connect from CLI #24593)

Related Issues

• [BUG] Claude-in-Chrome: Browser extension persistently fails to connect from CLI #24593 — Same bridge token validation bug, workaround exists for CLI but not Desktop
• [BUG] [BUG] Claude in Chrome extension fails to connect - "account mismatch" error despite same account on both extension and Claude Desktop #33660 — Identical symptoms, closed as "not about Claude Code" without resolution
• Claude in Chrome: account mismatch on cold Chrome start from Cowork (no retry on bridge connect) #36620 — Similar error but attributed to race condition (cold Chrome start); this issue persists even with Chrome fully loaded
• [BUG] Claude in Chrome: Intermittent "Check your Claude in Chrome account" dialog - native host EOF disconnects #32132 — Intermittent variant; this issue is persistent, not intermittent

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Update (2026-04-04): CLI workaround also broken now

The CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1 claude --chrome workaround that previously worked for CLI has stopped working as of v2.1.92.

New findings from debug log analysis

Using claude --chrome --debug-file, the actual error is now visible:

[Claude in Chrome] Connecting to bridge: wss://bridge.claudeusercontent.com/chrome/30c28730-bbdb-4107-bd94-a9f0779e957c
[Claude in Chrome] WebSocket connected, sending connect message
[Claude in Chrome] Bridge received: {"type":"error","error":"Invalid token or user mismatch"}
[Claude in Chrome] Bridge connection closed (code: 1008, duration: 0ms)

The WebSocket handshake succeeds but the bridge server immediately rejects the auth with "Invalid token or user mismatch".

Exhaustive client-side troubleshooting (all failed)

• claude auth logout + claude auth login (fresh OAuth token with user:sessions:claude_code scope confirmed in Keychain)
• Chrome extension logout + re-login
• Clear all claude.ai cookies + full re-auth both sides
• Remove & reinstall Chrome extension
• Remove Claude.app native host conflict (com.anthropic.claude_browser_extension.json)
• Migrate from x86 (Rosetta) to native ARM — not the cause
• Switch from npm-global to native binary install — not the cause
• Fix installMethod from native to npm-global — not the cause

Current environment

• Claude Code: v2.1.92 (native arm64 binary)
• macOS Darwin 25.4.0, Apple M4
• Chrome Extension: v1.0.66
• Auth: claude.ai Max plan, partylogo@gmail.com
• OAuth token confirmed in Keychain with correct scopes

Conclusion

This is a server-side issue with the bridge at wss://bridge.claudeusercontent.com. No client-side action resolves it. Both CLI and Desktop are affected — there is now zero workaround available.

See also: #43546 (filed today with full details, marked as duplicate)

[Adamsko11]

Account email: himmera1@gmail.com
Organization ID: bee54ba0-51e9-42b8-ad2f-fb54c71010fc
OS: Windows 11
Claude Desktop: latest (installed/updated 2026-04-29)
Chrome extension: "Claude" v1.0.69, ID fcoeoabgfenejglbffodgkkbkcdhcgfn
Issue
When Cowork mode tries to use the Claude in Chrome MCP, every browser tool call fails with "Claude in Chrome is not connected." The Chrome extension is installed, signed in, and reaching Anthropic's bridge service — but the bridge is rejecting the connection with a 403.
Exact error from %APPDATA%\Claude\logs\main.log:
2026-04-29 08:41:19 [info] [Claude in Chrome] Connecting to bridge: wss://bridge.claudeusercontent.com/chrome/b44be1cc-634c-4def-95bf-f4aec04e12d4
2026-04-29 08:41:19 [info] [Claude in Chrome] WebSocket connected, sending connect message
2026-04-29 08:41:19 [warn] [Claude in Chrome] Bridge error: OAuth token forbidden (403) — missing scope or org access
2026-04-29 08:41:19 [info] [Claude in Chrome] Bridge connection closed (code: 1008, duration: 0ms)
This repeats on every retry, including after a full sign-out / sign-in cycle on Claude Desktop.
Diagnostics already verified (all green)

Native messaging host registry key present at HKCU\Software\Google\Chrome\NativeMessagingHosts\com.anthropic.claude_browser_extension
Manifest JSON valid, points to existing helper exe at C:\Users\Adam Main\AppData\Roaming\Claude\ChromeNativeHost\chrome-native-host.exe
Helper exe present, dated 2026-04-29
Extension ID fcoeoabgfenejglbffodgkkbkcdhcgfn matches allowed_origins in the manifest
Chrome and Claude Desktop both running
Killed all stale processes (had 10 zombie Claude.exe instances) and restarted clean — same 403
Signed out and back in to Claude Desktop — same 403

The local chain is intact end-to-end. The rejection is server-side at the bridge.
What I need
Please verify whether the Cowork (Claude in Chrome) scope is provisioned for org bee54ba0-51e9-42b8-ad2f-fb54c71010fc, and if not, enable it. Cowork is in research preview, so I assume my org may not be in the rollout cohort yet — confirmation either way would let me stop debugging this locally.