AttributeError: '_tkinter.tkapp' object has no attribute 'block_update_dimensions_event'

I have an application that opens multiple windows, and when running on Windows 10 with Python3.9, opening a second window causes this error:

Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.9_3.9.3568.0_x64__qbz5n2kfra8p0\lib\tkinter\__init__.py", line 1892, in __call__
    return self.func(*args)
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.9_3.9.3568.0_x64__qbz5n2kfra8p0\lib\tkinter\__init__.py", line 814, in callit
    func(*args)
  File "C:\Users\Zico\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\customtkinter\windows\widgets\scaling\scaling_tracker.py", line 186, in check_dpi_scaling
    window.block_update_dimensions_event()
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.9_3.9.3568.0_x64__qbz5n2kfra8p0\lib\tkinter\__init__.py", line 2354, in __getattr__
    return getattr(self.tk, attr)
AttributeError: '_tkinter.tkapp' object has no attribute 'block_update_dimensions_event'

I've tried researching this, but I can't find anything. To my knowledge, I'm not missing any packages. I've uninstalled and reinstalled python, as well as tried this on multiple computers.

Start with the traceback location in customtkinter/windows/widgets/scaling/scaling_tracker.py at line 186 and inspect how windows are tracked during DPI-scaling checks. Reproduce the reported Windows 10/Python 3.9 case by opening a second window, then determine what allows the callback to call the missing method; done means the callback no longer raises this AttributeError.