[BUG] Desktop app (Electron) swallows Ctrl+Shift+C — no clipboard copy, no workaround

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

Not a duplicate of #38751 or #40080

• #38751 is about VS Code terminal hotkey capture — a different surface area (VS Code extension, not Electron app).
• #40080 (my earlier report) was auto-closed as a duplicate of #38751, but I cannot reopen it. This is a fresh filing with additional investigation.

What's Wrong?

In the standalone Claude Code desktop app (Windows, Electron), pressing Ctrl+Shift+C with text selected does nothing. The keypress is intercepted by the keybinding layer and swallowed — it never reaches the Electron/OS clipboard handler.

Workaround investigation: ~/.claude/keybindings.json only supports Claude Code UI actions (chat:submit, app:interrupt, app:exit, etc.). There is no clipboard:copy action and no pass-through/noop mechanism. Users cannot work around this via configuration.

Why this matters: Ctrl+Shift+C is the standard copy shortcut in every major terminal emulator on Windows (Windows Terminal, VS Code integrated terminal, Git Bash, PuTTY) because Ctrl+C is reserved for SIGINT. Users who switch between Claude Code desktop and a terminal have Ctrl+Shift+C as muscle memory for copy. When it silently does nothing, you think you copied text, switch apps to paste, and get stale clipboard contents.

What Should Happen?

Either:

1. Unbound key combinations should fall through to Electron/OS default handlers instead of being swallowed, or
2. A clipboard:copy action should be added to the keybindings system so users can bind it themselves

Steps to Reproduce

1. Open the Claude Code desktop app on Windows
2. Select any text in the conversation
3. Press Ctrl+Shift+C
4. Paste in another application → clipboard has stale contents, not the selected text
5. Press Ctrl+C instead → works correctly

Claude Model

N/A

Is this a regression?

I don't know

Claude Code Version

2.1.85

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

N/A (desktop app, not terminal)