[BUG] [Windows] Computer use still breaks Microsoft Pinyin IME candidate window (re-file of #69887, closed as stale)

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?

After Claude uses computer use on Windows, the Microsoft Pinyin IME candidate window stops appearing in every app, so Chinese text can't be composed. ctfmon.exe, ChsIME.exe and TextInputHost.exe are all still running, and IME settings are unchanged.

This is the same bug as #69887, which github-actions auto-closed as stale on 2026-08-02 and has since locked. It is still not fixed. It keeps coming back: I had to apply the workaround below on 2026-09-23, 09-25 and 09-26.

In the same session the main Claude window was also stuck always-on-top after computer use (see #95580). The hidden full-screen computer-use overlay window stays WS_EX_TOPMOST (ex-style 0x08280028). I don't know whether the two issues share a cause.

What Should Happen?

After computer use ends, the IME should work normally and the candidate window should appear when typing Pinyin. Computer use should restore/re-associate the IME input context after synthetic keyboard input, as suggested in #69887.

Error Messages/Logs

No error messages are shown. Workaround: killing TextInputHost.exe (Windows restarts it automatically) restores the candidate window until the next computer-use session:

powershell -NoProfile -Command "Stop-Process -Name TextInputHost -Force"

Steps to Reproduce

1. On Windows 11 with Microsoft Pinyin as the active input method, open Claude Desktop.
2. Start a session and give Claude a task that uses computer use (screenshots, clicks, typing/key presses in a desktop app).
3. Let the computer-use task finish.
4. Click into any text field (Notepad, browser, or the Claude input box) and type Pinyin, e.g. "nihao".
5. Observe: no candidate window appears, and Chinese characters can't be selected.

Temporary Fix: Kill TextInputHost.exe. The candidate window works again until the next computer-use session.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.280, Claude Desktop 2.7032.0.0 (MSIX)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_