[Bug] Claude in Chrome MCP "not connected" — Claude Code messaging host file never installed on macOS (Apple Silicon)

TL;DR

Fresh macOS install with both Claude Desktop AND Claude Code → Chrome native messaging directory contains ONLY Desktop's host config (com.anthropic.claude_browser_extension.json). NO Claude Code messaging host file (com.anthropic.claude_code_browser_extension.json) ever gets installed. Result: Claude Code's mcp__Claude_in_Chrome__* tools always return "not connected" because Chrome has nowhere to route Claude Code traffic.

Repro environment

• OS: macOS Sequoia 26 · Apple Silicon
• Chrome: latest stable
• Claude Desktop: /Applications/Claude.app v1.7196.0 · running pid 3828 (auto-starts on login)
• Claude Code: ~/Library/Application Support/Claude/claude-code/2.1.138/
• Claude in Chrome extension: installed · signed in · extension ID fcoeoabgfenejglbffodgkkbkcdhcgfn
• In-browser Claude sidebar: works perfectly (Desktop-routed)

Evidence

1. Chrome NativeMessagingHosts dir — ONLY Desktop's host registered

$ ls -la ~/Library/Application\ Support/Google/Chrome/NativeMessagingHosts/ | grep -i anthropic
-rw-r--r--   1 jeets  staff   411 May 18 02:19 com.anthropic.claude_browser_extension.json

NO com.anthropic.claude_code_browser_extension.json file exists. Anywhere.

2. Desktop's host config points back at Claude.app helper

$ cat ~/Library/Application\ Support/Google/Chrome/NativeMessagingHosts/com.anthropic.claude_browser_extension.json
{
  "name": "com.anthropic.claude_browser_extension",
  "description": "Claude Browser Extension Native Host",
  "path": "/Applications/Claude.app/Contents/Helpers/chrome-native-host",
  "type": "stdio",
  "allowed_origins": [
    "chrome-extension://dihbgbndebgnbjfmelmegjepbnkhlgni/",
    "chrome-extension://fcoeoabgfenejglbffodgkkbkcdhcgfn/",
    "chrome-extension://dngcpimnedloihjnnfngkgjoidhnaolf/"
  ]
}

Extension routes to Claude.app · NOT Claude Code.

3. Claude Code has no installer / register command for browser

$ claude --help 2>&1 | grep -iE 'chrome|browser|extension|install'
(no output · no flags exist)

4. Claude Code install dir has no chrome-native-host helper binary

$ find ~/Library/Application\ Support/Claude/claude-code -name "*chrome*" -o -name "*browser*" -o -name "*native_messag*"
(no output · no helper shipped)

5. MCP probes from Claude Code all fail same way

mcp__Claude_in_Chrome__tabs_context_mcp → "Claude in Chrome is not connected"
mcp__Claude_in_Chrome__list_connected_browsers → "Claude in Chrome is not connected"
mcp__Claude_in_Chrome__switch_browser → "Claude in Chrome is not connected"

Even switch_browser (which the tool description says broadcasts a connection request) fails — meaning the request never reaches the extension.

Expected behavior

When Claude Code is installed alongside Claude Desktop · either:

1. Claude Code installer should also install a com.anthropic.claude_code_browser_extension.json messaging host config + ship a chrome-native-host helper binary
2. OR Claude Code should fall back to using Claude Desktop's helper as a relay
3. OR Claude Code CLI should expose an explicit claude --install-chrome-bridge command that creates the messaging host config on demand

Current behavior: Claude Code MCP browser tools are silently non-functional on any Mac install where Claude Desktop is also present (which is the common case).

Related issues

• #20887 — Extension connects to Claude Desktop instead of Claude Code when both installed
• #20683 — MCP bridge not connecting when Claude.app is also installed
• #21279 — Browser extension not connected despite being connected
• #21331 — Connection fails despite extension installed and working
• #29528 — Browser extension not connected despite correct setup
• #54211 — MCP returns "not connected" despite all plumbing healthy
• #56241 — Bridge pairing state broken server-side for 7+ weeks · acknowledged backend issue

Multiple users · 6+ weeks open · no engineer action per the comments.

Workarounds I've validated

• ✓ In-browser Claude sidebar works (Desktop-routed) for DOM interaction
• ✓ Control Chrome MCP (mcp__Control_Chrome__*) works for navigation + JS exec (AppleScript-based · different transport)
• ✗ Quitting Claude Desktop does NOT help (Code still has no messaging host file installed)
• ✗ Restarting Chrome does NOT help (still no Code messaging host config to read)
• ✗ Reinstalling extension does NOT help

Ask

Ship a Claude Code installer step that registers the messaging host file + helper binary. Or document the manual creation steps in https://code.claude.com/docs/en/chrome.