There's a bug in the New Case / Upper case method

Everytime I add a bunch of files, and use New Case method > Set upper case. A lot of them warns in red: "Possibility of multiple files with the same name", but there's no other files with the same name in the same directory (and I'm only changing the names to upper case). It only happens using this New Case method...

I'm using the latest version 3.82.

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