URL: https://developer.apple.com/videos/play/wwdc2019/702/

Browser / Version: Firefox 69.0
Operating System: Windows 10
Tested Another Browser: Yes

Problem type: Video or audio doesn't play
Description: Apple HLS video stream doesn't play in Firefox
Steps to Reproduce:
This Apple video plays correctly in Chrome 76 and Edge on Windows 10, but not Firefox. Firefox shows an error message: "No video with supported format and MIME type found."

This video stream uses HLS (.m3u8), which is not supported by Firefox (Android or desktop). So not playing in Firefox is not a surprise, except desktop Chrome doesn't support HLS (according to Wikipedia and Can I Use) either and the stream plays correctly in desktop Chrome. (HLS is supported natively by Android Chrome and desktop Edge.) Perhaps this Apple site is using an HLS polyfill (like HLS.js) in desktop Chrome, but that should also work in Firefox and it doesn't (even if I spoof Chrome's UA in Firefox).

Firefox's web console shows an interesting non-video error message I don't see in Chrome or Edge:

SyntaxError: invalid regexp group play.js:1:2

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