This page exemplifies an error when downloading #6 in Firefox 47.0. The combination of of HTTPS, Gzip, and Service Worker do not allow the file to download successfully. Firefox shows a pop-up with error "[filename] could not be saved, because the source file could not be read."
Gzip compression is enabled by Nginx, and PHP is used to stream a text file. This download problem also occurred using a Python back-end to dynamically stream a file, but this server does not provide Python support.
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