[BUG] Unable to copy on terminal

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?

Copy functionality broken in Claude Code over SSH (macOS → Ubuntu); paste works but copy does not

Environment:

Local machine: macOS 15.7.7
Remote machine: Ubuntu (Linux 6.8.0-134-generic)
Claude Code version: 2.1.201
Connection: SSH from macOS into Ubuntu

Issue:

When running Claude Code over SSH from macOS to Ubuntu, the copy functionality is completely broken while paste works fine. This only affects Claude Code — copying works normally outside of Claude Code in the terminal.

Behavior:

Inside Claude Code TUI: Copy is broken (Ctrl+Shift+C does nothing, copy button greyed out)
Inside Claude Code TUI: Paste works fine (Ctrl+V works)
Outside Claude Code in terminal: Both copy and paste work normally
This occurs specifically when Claude Code is running; clipboard functions normally before/after

Current workaround:

Run Claude Code, then use tmux to switch windows, copy the output there (where clipboard works), paste into a file, then manually retrieve it. This is extremely cumbersome and defeats the purpose of an interactive CLI.

What Should Happen?

Expected behavior:

Copy should work inside Claude Code TUI over SSH, just as it does in the terminal outside Claude Code.

Error Messages/Logs

Steps to Reproduce

Reproduction steps:

SSH from macOS into Ubuntu box
Launch Claude Code with claude
Try to highlight copy text from Claude Code output (either via mouse selection or Ctrl+Shift+C)
Attempt to paste elsewhere — clipboard is unchanged
Exit Claude Code
Try to copy and paste from terminal — works fine

Claude Model

_No response_

Is this a regression?

I don't know

Last Working Version

Unsure version but worked in previous version to this one.

Claude Code Version

2.1.201

Platform

Other

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_