Windows 'Edit with IDLE' fails in one directory

[terryjreedy]

Bug report

f:\dev\3x>py -m idlelib f:/dev/tem/blank.py opens blank.py in IDLE. But in File Explorer, right click on blank.py and selection of `Edit with IDLE => Edit with IDLE 3.13 (64 bit) fails. Nothing happens. Same for 3.12 and 3.11.

Copy blank.py up to f:/tem and Edit with IDLE works. Neither directory has __init__ and __main__ defined. Looking at all tabs of the respective properties dialogs and the only difference I noted was the content file and bytes numbers. Context-menu opening works in another existing dir, with the two dunders defined.

If .../tem is renamed or copied (and - removed from the copy name), the command-line success and context-menu failure remain. It seems to be poisoned somehow. With a new subdirectory, F:/dev/temNew with blank.py copied into it, context-menu selection works.

[terryjreedy]

I am pretty sure that this is not an idlelib issue, but I want to keep track of it.