Chrome extension won't reconnect after possible tab group deletion (Windows)

Description

The Claude in Chrome browser extension stopped connecting to Claude Code. The tabs_context_mcp call consistently returns "Browser extension is not connected."

The issue may have started after manually deleting/closing a Claude tab group in Chrome, though this is not confirmed as the root cause. Claude Desktop was also installed alongside Claude Code, which left a conflicting native messaging host registry entry — this has since been resolved but did not fix the connection issue.

What Happened

• The Chrome extension was previously working with Claude Code
• At some point the connection broke and has not recovered
• The suspected trigger was deleting a Claude tab group in Chrome, but this may be coincidental

Troubleshooting Attempted (none resolved the issue)

• Killed all Chrome processes (taskkill /F /IM chrome.exe /T) and restarted Chrome
• Restarted Claude Code across multiple sessions
• Ran /chrome command in Claude Code
• Verified extension is installed and enabled in chrome://extensions/
• Verified correct Chrome profile is active
• Uninstalled Claude Desktop
• Removed conflicting Claude Desktop native messaging host registry entry (HKCU\SOFTWARE\Google\Chrome\NativeMessagingHosts\com.anthropic.claude_browser_extension)
• Verified Claude Code's native messaging host config, batch file, and extension directory all exist and are correctly configured
• Restarted both Chrome and Claude Code in various orders

Environment

• OS: Windows 10 (Build 26200.7623)
• Extension ID: fcoeoabgfenejglbffodgkkbkcdhcgfn
• Native host path: C:\Users\gary\.claude\chrome\chrome-native-host.bat

Related Issues

• #20546 — Claude Desktop and Claude Code competing for the same extension (registry conflict was resolved but didn't fix the issue)
• #20298 — General "extension not connected" issue
• #20862 — /chrome shows connected but tools fail
• #15527 — Connection only works after restarting Chrome during active session