C:\Program Files\Git\desktop fails on Windows even when Claude desktop app is installed and claude;\ protocol works

Summary

The /desktop slash command in Claude Code CLI fails on Windows with Error: Failed to open Claude Desktop. Please try opening it manually. even though the Claude desktop app is correctly installed and the claude:// protocol handler is registered and functional.

Environment

• OS: Windows 11 Pro 10.0.26200
• Shell: PowerShell 5.1
• Claude Code CLI version: 2.1.146 (also reproduced on 2.1.142/143/145 present in ~/.local/share/claude/versions/)
• Claude desktop app: installed at C:\Users\<user>\AppData\Local\AnthropicClaude\claude.exe (app-1.8089.1)

Repro

1. Install the Claude desktop app from https://clau.de/desktop
2. In Claude Code CLI, run /desktop
3. Observe: Error: Failed to open Claude Desktop. Please try opening it manually.

What works (so it's not a missing install / broken protocol)

• Launching the app directly via Start-Process "C:\Users\<user>\AppData\Local\AnthropicClaude\claude.exe" opens the app cleanly
• The claude:// protocol handler is correctly registered in HKCU\Software\Classes\claude\shell\open\command pointing at the versioned exe and Start-Process \"claude://\" opens the app
• Re-running /desktop after a fresh CLI restart still fails

Expected

/desktop hands the current CLI session off to the desktop app, or at minimum opens it.

Actual

The CLI prints the failure message and the desktop app is not launched.

Notes

Looks like the /desktop detection or launch path on Windows is checking for something other than the protocol handler / standard install path, since both are present and working.