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https://forums.plex.tv/t/bug-fire-tv-wont-play-srt-if-ass-present/710315/6
https://forums.plex.tv/t/mkv-files-embedded-ass-subtitles-always-shown-on-fire-tv-4k-cube-client/716324
https://forums.plex.tv/t/mobile-app-pulling-from-non-existent-subtitle-file/712611
