I tried with a lot of files.
If I have accents, spaces, or special characters, I have the issue. But if my files are no spaces, etc. the file name downloaded is right.
If I rename the file under the Resource Manager without spaces, etc. the file name downloaded is right. Conversely, if I rename the file under the Resource Manager with a space, etc. the file name downloaded has the issue.
I also tried with a new Uploaded file, and I have the same issue.
I agree with you to create a new issue but before that, I just would like to know if the issue is only with me.