URL: http://pbskids.org/daniel/videos/

Browser / Version: Firefox 60.0
Operating System: Mac OS X 10.13
Tested Another Browser: Unknown

Problem type: Video or audio doesn't play
Description: Video doesn't play
Steps to Reproduce:
Open URL in a fresh profile
Video plays for a moment and then a "OOPS!" message pops up

Console has:

Cannot play media. No decoders for requested formats: application/x-mpegURL, application/vnd.apple.mpegURL, video/m3u8 videos
HTTP “Content-Type” of “application/x-mpegurl” is not supported. Load of media resource https://kids.video.cdn.pbs.org/../filename.m3u8 failed.

(Resource URL redacted)

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