[BUG] Claude Desktop app launches but no window appears - MacBook Pro M3 (macOS Tahoe 26.5)

Preflight Checklist

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

What's Wrong?

Claude Desktop app launches (Dock shows dot + "Claude" appears in menu bar) but no window ever appears. The Window menu is completely empty.

Error messages from verbose logging:

• locale_file_path.empty() for locale ko-KR
• Failed initializing First-Party Sets database
• OspreyKeychain saveData:withIdentifier: Failed to save data

Environment:

• MacBook Pro 14 (2023), Apple M3 Pro, 18GB RAM
• macOS Tahoe 26.5
• Claude Desktop app (latest version)

What I've tried:

• Reinstalled app multiple times
• Deleted all Library files (Application Support, Preferences, Caches, Saved State, Logs)
• Ran with --disable-gpu and --no-sandbox flags
• Changed system language to English and reinstalled
• Deleted "Claude Safe Storage" from Keychain Access
• Ran with LANG=en_US.UTF-8

Note: Same Apple account works fine on another MacBook Pro 14 (M3, company laptop) on macOS Sequoia 15.7.5.

What Should Happen?

When the app is launched, a window should appear so the user can log in and use Claude Desktop normally.

Error Messages/Logs

locale_file_path.empty() for locale ko-KR
Failed initializing First-Party Sets database
OspreyKeychain saveData:withIdentifier: Failed to save data

Steps to Reproduce

1. Install Claude Desktop app on MacBook Pro 14 (M3, macOS Tahoe 26.5)
2. Launch the app
3. App appears in Dock with a dot and "Claude" shows in menu bar
4. No window appears - Window menu is completely empty

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

N/A - Claude Desktop app issue, not Claude Code

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

This is a Claude Desktop app issue, not Claude Code. The app has never worked on this machine since first install. Verbose terminal logging shows locale and keychain errors but no fatal crash.
Note: This issue also occurred on macOS Sequoia 15.7.5 before upgrading to Tahoe 26.5. This is NOT a Tahoe-only issue.