Chrome extension never registers with the bridge: list_connected_browsers always "not connected" (ext 1.0.100 / CLI 2.1.299 / macOS 15)

Summary

CLI launched with --chrome. The extension is installed, enabled, up to date (1.0.100) and signed in to claude.ai with the same account as Claude Code, but list_connected_browsers always returns "Browser extension is not connected". The extension never registers with the bridge.

Debug log

The CLI creates the bridge room and gives up after 10s:

[INFO] Bridge URL: wss://bridge.claudeusercontent.com
[Claude in Chrome] Connecting to bridge: wss://bridge.claudeusercontent.com/chrome/<account-uuid>
(10s later) Connection timeout, connected=false, authenticated=false
[ERROR] Failed to flush logs to Datadog: timeout of 5000ms exceeded

Ruled out locally

• Network: WS handshake to bridge.claudeusercontent.com returns 101 Switching Protocols (6/6 attempts, curl --http1.1).
• TLS from Node: tls.connect to the bridge gives authorized=true, cert issued by Google Trust Services — no MITM / corporate interception on that host.
• Account match: the extension's Local Extension Settings and claude.ai localStorage both hold the CLI's account uuid.
• Feature gate: extension storage contains "chrome_ext_bridge_enabled":{"source":"defaultValue","value":true}.
• Extension version: 1.0.100; pressing "Update" on chrome://extensions produces no change.
• Restarts: Chrome restarted 3x; CLI restarted with --chrome (also via --resume <id> --chrome); extension uninstalled and reinstalled.
• Service worker: no errors in its console.
• Native messaging: Claude Desktop's com.anthropic.claude_browser_extension.json moved aside to rule out contention — no effect, consistent with the CLI using the bridge path only. claude.exe --chrome-native-host does spawn and listen on /tmp/claude-mcp-browser-bridge-<user>/<pid>.sock, but no session ever connects to it.
• Profiles: several Chrome profiles have the extension; the active one holds the matching account uuid and a bridgeDeviceId.

Ordering was also tested both ways (extension registered before the CLI started, and vice versa).

Environment

| | |
|---|---|
| OS | macOS 15.5 (Darwin 25.5.0), arm64 |
| Chrome | 155.0.8059.41 |
| Extension | Claude in Chrome 1.0.100 |
| Claude Code | 2.1.299 (volta install, installMethod: global) |
| Other | Netskope and Cisco AnyConnect system extensions present (WS to the bridge still returns 101) |