Please see jkingsman#12 (comment) -- tl;dr I can't keep up the cat and mouse game so I'm gonna archive this project.
Safari extension by WarningImHack3r (Requires a Mac with Xcode)
This Chrome extension creates a download button on media pages within plex to enable non-media-owners to download files.
This extension only works on video files, not music or other media, although the download button does also appear on non-downloadable files.
This extension is essentially a wrapper around Pip Longrun's pip.longrun@protonmail.com Plex Downloader, which is MIT licensed.