Cannot download a file with a capitalized extension

[paul-arg]

Hello,

First of all thank you for this amazing tool.

I tried uploading the following file: file.EPUB. The file was uploaded correctly and visible on the Kobo, but when I clicked on the download link, nothing happened.

I renamed the file to file.epub and it worked correctly.

Sometimes EPUB or PDF files I download from the internet have capitalized extensions so this might occur with other people too.