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I suspect based on other more recent reports that the Tk window was coming up behind the IDE window, particularly if on macOS. If true, this may help:
import tkinter as tk
from tkinter import messagebox
# Set up Tk top-level to defeat macOS window order issues when debugging
import sys
if hasattr(sys, '_wing_debugger'):
_root = tk.Tk()
_root.withdraw()
sw = _root.winfo_screenwidth()
sh = _root.winfo_screenheight()
_root.geometry(f'1x1+{sw // 2}+{sh // 3}')
_root.deiconify()
print(messagebox.askyesno('title', 'question'))