Non-English title broken when saving to disk

[W-rakuda]

Describe the bug/problem

Calibre-web no longer serves downloads with non-English filenames regardless of option "Convert non-English characters in title and author while saving to disk" being set or not.

To Reproduce

Steps to reproduce the behavior:

1. Click Download on book with non-English filename.
2. Receive file with transliterated title.

Expected behavior

Filenames contain non-English characters.

Environment (please complete the following information):

• Calibre-Web version: 0.6.26
• Docker container: LinuxServer