In launcher.exe, the Tkinter messagebox displays the classic style.

[Jesse205]

Install source and version

• Installed from the Windows Store
• Installed with the MSIX from python.org
• Installed with the MSI from python.org
• Installed with winget install 9N7512CXL7T

Version: 26.1

Describe the bug
A clear and concise description of what the bug is.

When creating a tkinter messagebox in Python launched by launcher.exe, the messagebox displays in the classic style, regardless of whether it is a console program.

To Reproduce
Steps to reproduce the behavior:

0. Install Python 3.14 using pymanager
1. Create tkinter-msgbox-example.py:

    import sys
    from tkinter import messagebox
   
    if sys.platform == "win32":
        from ctypes import windll
   
        windll.user32.SetProcessDPIAware()
   
    messagebox.showinfo(title="Example",message="Hello world")

2. Navigate to the folder: C:\Users\USER\AppData\Local\Python\bin
3. Drag tkinter-msgbox-example.py onto python.exe or pythonw.exe

Expected behavior
A clear and concise description of what you expected to happen.

Display in the modern style, just like when running pymanager or running the Python interpreter directly.

Additional context
If you have log files (check your %TEMP% directory!), drag-and-drop them here to include them.

[Jesse205]

The latest 26.2b1 also has the issue (I did not perform a real installation test; I tested it by extracting the MSIX and manually creating launcher-64.exe.__target__ to templates).