NO_FLICKER: Mouse click-to-position cursor not working in input box on Windows 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?

Environment

• Claude Code version: 2.1.90
• OS: Windows 11 Home 10.0.26200
• Terminal: Windows Terminal (PowerShell Core / Windows.Terminal.PowershellCore)
• TERM: xterm-256color
• WT_SESSION: present (confirmed Windows Terminal session)

Configuration

CLAUDE_CODE_NO_FLICKER=1 (set as user environment variable)
CLAUDE_CODE_DISABLE_MOUSE is NOT set

What's happening

With CLAUDE_CODE_NO_FLICKER=1 enabled, the fullscreen/alternate screen buffer mode is active and working — the display is visibly different and mouse wheel scrolling works correctly.

However, clicking inside the input box does NOT move the text cursor to the clicked position. The cursor stays in place.

Steps to reproduce

1. Set CLAUDE_CODE_NO_FLICKER=1 as environment variable
2. Launch claude from Windows Terminal (PowerShell Core tab)
3. Type some text in the input box (don't submit)
4. Click somewhere in the middle of the typed text
5. Expected: Cursor moves to clicked position
6. Actual: Cursor stays where it was — does not move

What works

• NO_FLICKER mode is active (display changed)
• Mouse wheel scrolling works
• Mouse click is detected (something responds)

What doesn't work

• Click-to-position cursor in the input box

Additional context

• Windows Terminal settings have no custom mouse restrictions
• No tmux or SSH — direct local terminal session
• Color scheme: Solarized Light

What Should Happen?

Clicking inside the input box in NO_FLICKER fullscreen mode should reposition the text cursor to the clicked position, as documented.

Error Messages/Logs

Steps to Reproduce

1. Set CLAUDE_CODE_NO_FLICKER=1 as environment variable
2. Launch claude from Windows Terminal (PowerShell Core tab)
3. Type some text in the input box (don't submit)
4. Click somewhere in the middle of the typed text
5. Observe: cursor does not move to clicked position

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.90 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_