[BUG] OSC terminal color query responses leak into input buffer

[austeane]

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?

Random strings appear in the input box while Claude is responding: ]11;rgb:1414/1414/1414]11;rgb:1414/1414/1414]10;rgb:e4e4/e4e4/e4e4\

These are OSC escape sequence responses:

• ]11;rgb:... - terminal background color response
• ]10;rgb:... - terminal foreground color response

Once that happens once, when I scroll up it scrolls through input prompts rather than through my chat history. In Ghostty, I can still do shift+scroll to scroll up properly.

What Should Happen?

Color query responses should be captured/suppressed, not appear in user input.

Error Messages/Logs

Steps to Reproduce

Environment:

• Claude Code version: 2.0.56 (native install)
• OS: macOS (26.1)
• Affected terminals: Terminal.app, Ghostty, Cursor integrated terminal

Relevant shell config (~/.zshrc):

  # Using zsh with:
  eval "$(/opt/homebrew/bin/brew shellenv)"
  eval "$(pyenv init -)"
  eval "$(zoxide init zsh)"

  # Starship disabled during debugging (issue persists without it)
  # eval "$(starship init zsh)"

  # zsh plugins
  source /opt/homebrew/share/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh
  source /opt/homebrew/share/zsh-autosuggestions/zsh-autosuggestions.zsh
  source ~/.fzf.zsh

claude doctor output: Diagnostics └ Currently running: native (2.0.56) └ Path: /Users/austin/.local/bin/claude └ Invoked: /Users/austin/.local/share/claude/versions/2.0.56 └ Config install method: native └ Auto-updates: default (true) └ Search: OK (bundled)

Occurs when resuming longer Claude some sessions, and in the middle of Claude responses. My guess is when a certain colour/process happens that doesn't always happen with short sessions.

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

(worked last week, but unknown if it was a regression in Claude Code or a change in my environment)

Claude Code Version

2.0.56 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS) + Ghostty + Cursor

Additional Information

Could be a change in my environment, but I think it's still a bug in Claude Code as e.g. Codex and other CLI tools have not been affected.

https://github.com/user-attachments/assets/23fb2a85-56bd-4a3f-9d6d-00a639f450ef

[github-actions[bot]]

Found 3 possible duplicate issues:

1. https://github.com/anthropics/claude-code/issues/10375
2. https://github.com/anthropics/claude-code/issues/1509
3. https://github.com/anthropics/claude-code/issues/9249

This issue will be automatically closed as a duplicate in 3 days.

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🤖 Generated with Claude Code

[austeane]

Similar but not quite the same as #1509, especially with the scrolling issue.

[github-actions[bot]]

This issue has been inactive for 30 days. If the issue is still occurring, please comment to let us know. Otherwise, this issue will be automatically closed in 30 days for housekeeping purposes.

[nhaynes]

I am also experiencing this issue on MacOS using iTerm2