[BUG] IDE-detection poll flashes a visible console window every ~15s on Windows

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?

Claude Code periodically shells out to detect which IDE/editor is running (checking for Code.exe, Cursor.exe, Windsurf.exe, various JetBrains *64.exe binaries, etc. via tasklist | findstr). On Windows, this spawns a visible cmd.exe console window that flashes on screen and disappears, roughly every 15 seconds, for the entire duration of any active session.

What Should Happen?

The IDE-detection check should run without ever showing a console window — e.g. by launching the subprocess with CREATE_NO_WINDOW / STARTF_USESHOWWINDOW (hidden) on Windows, the way other background subprocess calls in Claude Code already appear to do.

Error Messages/Logs

Steps to Reproduce

Run Claude Code on Windows (observed on claude-code v2.1.197).
Leave a session open/active.
Watch the taskbar / desktop — a cmd.exe window flashes into view and closes roughly every 15 seconds.
Confirmed via process inspection: the flashing cmd.exe runs

cmd.exe /d /s /c "tasklist | findstr /I "Code.exe Cursor.exe Windsurf.exe Devin.exe idea64.exe pycharm64.exe webstorm64.exe phpstorm64.exe rubymine64.exe clion64.exe goland64.exe rider64.exe datagrip64.exe appcode.exe dataspell64.exe aqua64.exe gateway64.exe fleet.exe studio64.exe""
with ParentProcessId pointing directly at the running claude.exe process for the session.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.197

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

This is purely cosmetic/annoying (no functional breakage observed) but is disruptive when actively working, since a console window steals focus-adjacent attention every 15 seconds.

Root cause was diagnosed by Claude itself, inside a live Claude Code session — it traced the flashing window to its own parent process via Get-CimInstance Win32_Process, found the tasklist/findstr IDE-detection command, and confirmed the parent PID matched the running claude.exe.