Claude in Chrome extension not connecting (native host registered correctly)

Environment

• OS: Windows 11 Pro 10.0.26200
• Claude in Chrome extension version: 1.0.90
• Extension ID: fcoeoabgfenejglbffodgkkbkcdhcgfn
• Claude Code: CLI session on win32

Problem
list_connected_browsers / tabs_context_mcp consistently return "Claude in Chrome is not connected", even after:

• Confirming the extension is enabled in chrome://extensions
• Logging into the extension's side panel with the same account used in Claude Code
• Fully closing and reopening Chrome
• Restarting the Claude Code session

Diagnostics already ruled out

• Firewall: Windows Firewall enabled on all profiles, but explicit Allow rules exist for both "Claude" (in/out) and "Google Chrome" (mDNS-In). No blocking rules found.
• Antivirus: Only Windows Defender registered (via SecurityCenter2), real-time protection on, no third-party AV present.
• Native messaging host registration: HKCU\SOFTWARE\Google\Chrome\NativeMessagingHosts\com.anthropic.claude_browser_extension exists and points to a valid manifest at

C:\Users\<user>\AppData\Local\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\ChromeNativeHost\com.anthropic.claude_browser_extension.json

• allowed_origins correctly includes chrome-extension://fcoeoabgfenejglbffodgkkbkcdhcgfn/
• Referenced executable chrome-native-host.exe exists on disk (last modified 2026-09-01)

Since registration, firewall, and AV all check out, the failure appears to be in the pairing/handshake between this specific Claude Code session and the extension's native host process (no chrome-native-host process was observed running, which may be expected if it's spawned on demand and failing to stay alive, or never being invoked).

Request
Guidance on how to further diagnose native-host handshake failures, or confirmation of a known issue with this extension version / CLI combination.