[BUG] Permission dialog dismissal corrupts terminal output — text from different lines merged/garbled (macOS Terminal.app)

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?

After dismissing a large permission dialog (the "Accept / Accept for this session / Deny" prompt for a Bash tool call), the screen redraws incorrectly, causing previously rendered output lines to merge together and produce garbled text.

In this case, a Bash command had errored (Exit code 1) and the model was in its "Imagining..." thinking phase. After accepting the permission prompt, the redraw merged the error line with the spinner/status line, producing:

✱ ImaError: Exit code 1↑ 225 tokens)
    Type: BidirectionalStrategyDefinition

The Ima prefix comes from Imagining... and Error: Exit code 1 comes from the Bash error output — they were rendered on top of each other. The token counter ↑ 225 tokens) was also displaced into the error line instead of rendering in its normal position.

What Should Happen?

After dismissing the permission dialog, the screen should redraw cleanly with each output element (error messages, spinner/status line, token counters) on their own separate lines without overlapping.

Steps to Reproduce

1. Start Claude Code in macOS Terminal.app
2. Trigger a workflow where a Bash tool call requires user permission (not pre-allowed)
3. Have the Bash command produce an error (exit code 1)
4. While the model is in its thinking/imagining phase, the permission dialog appears
5. Accept the permission ("Yes" or "Accept for this session")
6. Observe the screen after redraw — error text and spinner/status text are merged on the same line

Error Messages/Logs

No error in logs — this is purely a visual/terminal rendering bug.

Screenshot

!Screenshot 2026-02-08 at 11 46 25 AM

Note: Screenshot shows the garbled ImaError: Exit code 1↑ 225 tokens) output after permission dialog dismissal.

Related Issues

Similar to #19637 (text overlapping and garbled display on Windows cmd), but this occurs on macOS Terminal.app and is specifically triggered by the permission dialog redraw rather than being a general rendering issue.

Also related to #769 (screen flickering during in-progress calls) and #17025 (progress lines repeating instead of updating in place).

Claude Model

Opus 4.6

Claude Code Version

2.1.37

Platform

• macOS 26.2 (Build 25C56)
• Terminal: macOS Terminal.app
• Installation: Anthropic API (direct)

Is this a regression?

Unknown — first time encountering this specific trigger.