Total Commander

Example.

Create folder "folder".
Create file and open it with LibreOffice to lock file.
Try to rename folder to "111". There is error (as expected).
Try to rename folder to "FOLDER". There is no error. And nothing happens.

Yes, that is exactly how Windows works !

Filenames at Windows are NOT case sensitive.
So "folder" and "FOLDER" is the same name at Windows!