claude-code - 💡(How to fix) Fix [BUG] Ink renderer crashes on Windows 11 build 26200 (Canary) duplicate banners, terminal mode leaks, mid-operation aborts

Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report (please file separate reports for different bugs)
• I am using the latest version of Claude Code

What's Wrong?

Claude Code's TUI renderer crashes on Windows 11 Canary build 26200, leaving the terminal in a broken state.

Two distinct crash patterns:

1. In PowerShell: the process exits immediately when the first interactive selection prompt renders (e.g., the "trust this folder?" menu). After the crash, terminal modes are not restored bracketed paste mode and focus reporting remain enabled, causing subsequent shell commands to show leaked escape sequences like ^[[200~, ^[[201~, and ^[[I.

2. In cmd.exe: startup partially works, but the launch banner sometimes renders twice and out of order, and the process dies mid-operation during multi-line Edit/Write tool calls (~30+ line diffs).

The crash happens with no error message and no apparent stack trace surfaced to the user the process just disappears and the terminal prompt returns.

What Should Happen?

The TUI should render interactive prompts and large tool-call diffs without crashing. On any exit (graceful or unexpected), terminal modes (raw input, bracketed paste, focus reporting) should be restored so the host shell continues to work normally.

Error Messages/Logs

No error message is printed. Process exits silently.

After PowerShell crash, terminal leaks escape sequences:

PS C:\Users\ribei\companion_core> claude
... [trust prompt renders] ...
> 1. Yes, I trust this folder
PS C:\Users\ribei\companion_core>^[[I

PS C:\Users\ribei\companion_core> ^[[200~npm view @anthropic-ai/claude-code versions^[[201~
'npm' is not recognized as an internal or external command, operable program or batch file.

In cmd.exe the startup banner sometimes duplicates:

 ▐▛███▜▌   Claude Code v2.1.153
▝▜█████▛▘  Sonnet 4.6 · Claude Pro
  ▘▘ ▝▝    ~\companion_core
▝▜█████▛▘  Sonnet 4.6 · Claude Pro
 ▐▛███▜▌   Claude Code v2.1.153
▝▜█████▛▘  Sonnet 4.6 · Claude Pro
  ▘▘ ▝▝    ~\companion_core

Steps to Reproduce

1. Windows 11 Canary build 10.0.26200.8457, Node v22.22.0, npm 11.13.0.
2. Install: npm i -g @anthropic-ai/[email protected]
3. Open PowerShell, cd into any project folder, run claude.
4. At the "Quick safety check / Yes, I trust this folder" prompt, observe the process exits before you can press Enter.
5. Type any command into PowerShell afterward — escape sequences leak into the prompt.

To reproduce Pattern B:

1. Open cmd.exe instead of PowerShell, run claude in the same folder.
2. Accept the trust prompt — works.
3. Ask Claude to perform a refactor that produces a multi-line Edit/Write tool call (~30+ changed lines).
4. Process dies mid-render. Same terminal-mode leak afterward.

Isolation tests confirming the issue is NOT generic raw-mode / TTY failure:

• node -e "process.stdin.setRawMode(true);process.stdin.on('data',d=>{console.log('byte',d[0]);if(d[0]===113){process.stdin.setRawMode(false);process.exit()}});console.log('press keys, q quits')" → works perfectly in both PowerShell and cmd.exe. Prints byte codes, exits cleanly on q.
• claude --version → works.
• Same crash on 2.1.148 and 2.1.153.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

No response

Claude Code Version

2.1.153

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information