[BUG] Banner redraws repeatedly when dragging/resizing window in PowerShell

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?

Version: v2.1.87
OS: Windows 11 Pro
Shell: PowerShell (pwsh)

Steps to reproduce:

1. Launch Claude Code in PowerShell
2. Drag/resize the window

Expected: Banner appears only once at startup
Actual: Welcome banner redraws every time the window is moved or resized

What Should Happen?

Steps to reproduce:

1. Launch Claude Code in PowerShell
2. Drag/resize the window

Expected: Banner appears only once at startup
Actual: Welcome banner redraws every time the window is moved or resized

Error Messages/Logs

Steps to Reproduce

PowerShellウィンドウをドラッグするたびにターミナルリサイズイベントが発生し、起動バナーが再描画されています。

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Version: v2.1.87

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_