Bug report

Using Toplevel wait_window from Tkinter on MacOS will cause the process to hang and the windows are never spawned. MRE follows:

import tkinter as tk

class MainWindow(tk.Tk):
  def __init__(self):
    super().__init__()
    self.title("Hello")
    tk.Label(self, text='Hi there').pack()

    self.after_idle(self.waitforit)
    self.mainloop()
  
  def waitforit(self):
    x = WaitedForWindow(self).show()
    print(x)

class WaitedForWindow(tk.Toplevel):
  def __init__(self, parent: tk.Tk):
    tk.Toplevel.__init__(self, parent)

    tk.Button(self, text='Press me', command=self.destroy).pack()

  def show(self):
    self.deiconify()
    self.wait_window()
    return True

if __name__ == "__main__":
  MainWindow()

Spawning a window (without calling the .show() above) will work fine, but a value cannot be returned of course, and both windows will spawn. Running the same MRE in 3.9.0 works fine.

• Potential troubleshooting steps: Test on a Big Sur (or, just higher than Mojave) machine with 3.11.1

Your environment

• CPython versions tested on:
  • 3.9.0 (working)
  • 3.10.9 (non-functional)
  • 3.11.1 (non-functional)
  • 3.12.0a3 (non-functional)
  • ... all 64-bit
• Operating system and architecture: MacOS Mojave 10.14.6 x64
• Tkinter version: 8.6.12
• 3.9.0, 3.11.1 tested in and out of bare virtualenv
• additional tests from colleagues:
  • W11, 3.10.5 (working)