Spellcheck cannot be disabled in Windows Desktop App (Store/WinGet version)

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?

The Claude Code desktop app uses Electron's built-in Chromium spellchecker, which cannot be disabled. It defaults to the Windows display language (German), marking all English input as incorrect with red underlines.

What Should Happen?

The spellcheck language should be configurable in app settings, or there should be an option to disable it entirely.

Error Messages/Logs

Steps to Reproduce

1. Install Claude Code via WinGet (winget install Anthropic.ClaudeCode)
2. Open the desktop app
3. Type any English text in the input field
4. All words are marked as misspelled (red underlines)

Attempted fixes that had no effect:

• Windows Settings → Typing → "Highlight misspelled words" = OFF
• Setting LANG environment variable to en-US
• Adding --lang=en-US flag to shortcut (ignored by Store-style app)
• Right-click context menu shows no spellcheck option

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

claude 2.1.78

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

N/A - issue occurs in the Claude Code Desktop GUI app only

The app is installed in WindowsApps\ (Store-style via WinGet), which prevents passing custom Electron flags via shortcuts. The only workaround is reinstalling via the PowerShell installer (install.ps1), which places the binary in ~/.local/bin and allows flag configuration.