Drag-n-Drop handling error on Windows, receiving a file on the app from an external app

[TrevorMarvinPNNL]

Bug report

Handling of a Drag-n-Drop event with tkinter causes an exception:

File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.10_3.10.1520.0_x64__qbz5n2kfra8p0\lib\tkinter\__init__.py", line 1920, in __call__
    args = self.subst(*args)
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.10_3.10.1520.0_x64__qbz5n2kfra8p0\lib\tkinter\__init__.py", line 1605, in _substitute
    e.serial = getint(nsign)  
_tkinter.TclError: expected integer but got "%#"

The basic code used is this (more code is in the app, but this should be the relevant parts of the setup):

def drop(event):
        print("DROP EVENT:", event) # test code to see what's delivered

root = tkinterDnD.Tk()
root.register_drop_target("*")
root.bind("<<Drop>>", drop)

The intent is to capture a file dragged from another application. With the 'register' function, this Python program and the OS indicate that the program's window is a valid place to drop a file dragged from a file manager program (specifically using Windows Explorer). After 'dropping', the error shown above is seen.

Your environment

• CPython versions tested on: Python.3.10_3.10.1520.0_x64__qbz5n2kfra8p0
• Operating system and architecture: Windows 10

[TrevorMarvinPNNL]

Might be related to another library. Closing until I can research this.