Korean IME: All Ctrl+key shortcuts silently ignored when Hangul input is active

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?

When the Korean (Hangul) IME is active, all Ctrl+key shortcuts are completely non-functional in Claude Code. This includes Ctrl+C, Ctrl+A, Ctrl+L, Ctrl+E, and every other Ctrl combination. Switching to English input mode immediately restores all shortcuts.

This is not a system-wide or terminal issue — the same shortcuts work perfectly in:

• Terminal.app (bare shell)
• iTerm2
• tmux

The problem only occurs inside Claude Code's TUI.

What Should Happen?

Ctrl+key shortcuts should work regardless of the active input source, as they do in standard terminal applications. Terminal emulators pass Ctrl+key as raw control characters (e.g., Ctrl+C = 0x03) independent of IME state.

Error Messages/Logs

No error messages — the shortcuts are silently ignored with no feedback.

Steps to Reproduce

1. Open Claude Code in any terminal (Terminal.app, iTerm2, etc.)
2. Switch macOS input source to Korean (한국어)
3. Try any Ctrl+key shortcut:

• Ctrl+C — Expected: interrupt/cancel → Actual: nothing
• Ctrl+A — Expected: cursor to line start → Actual: nothing
• Ctrl+L — Expected: clear screen → Actual: nothing
• Ctrl+E — Expected: cursor to line end → Actual: nothing

1. Switch input source back to English
2. All shortcuts work again

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Claude Code Version

2.1.86 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

• Terminal used: cmux (Ghostty/libghostty-based macOS terminal)
• Also tested in Terminal.app, iTerm2 — same behavior in all terminals.

Workaround: Using Karabiner-Elements to intercept Ctrl+key at the OS level — temporarily switching to English, sending the shortcut, then switching back to Korean. This is an OS-level hack, not a proper fix — the issue should be resolved in Claude Code's input handling layer.