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It was indeed an encoding issue.
Opening with Notepad++ (I’ve managed to open it from a PC), I’ve realized that the file was encoded as UCS-2 something (I don’t remember exactly if Big or Little Endian).

I have no idea why this happened and how to avoid that in the future, as I’ve simply created this file from an existing file that has the right encoding (ANSI): I’ll investigate with JetBrains support to see if they can find a possible cause.

Thanks everybody!