Console popup windows from internal npm/process operations on Windows

Description

Claude Code on Windows (VS Code extension) spawns brief console popup windows (black cmd.exe flashes) during sessions. These appear both at startup and during tool use. The popups show commands like npm root and other internal operations.

Environment

• OS: Windows 11 Home 10.0.26200
• VS Code: 1.115.0 (user setup)
• Claude Code: VS Code extension (latest)
• Shell: Git Bash

What I've tried

• All user-configured hooks already use pythonw.exe (GUI subsystem, no console window)
• All MCP servers use pythonw + a wrapper script with CREATE_NO_WINDOW flag
• The popups are NOT from user hooks or MCP servers — they come from CC's own internal process spawning

Steps to reproduce

1. Install Claude Code VS Code extension on Windows
2. Open a project with hooks and MCP servers configured
3. Start a session — console windows flash on screen
4. Use any tool (Read, Edit, Bash, etc.) — more console windows flash

Expected behavior

No visible console windows. Internal process operations should use CREATE_NO_WINDOW or pythonw/windowless subsystem when spawning child processes on Windows.

Actual behavior

Brief black console popup windows appear repeatedly during sessions, interrupting focus. At least one popup shows npm root as the command being executed.

Notes

This does not occur on Linux (no console window concept). The issue is specific to Windows where console-subsystem executables (python.exe, node.exe, npm.cmd) create visible windows when spawned by a GUI application (VS Code extension host).