URL: www.foxnews.com
Browser / Version: Firefox Mobile Nightly 55.0a1 (2017-03-27)
Operating System: Samsung Galaxy Note 4 (Android 5.0.1)
Problem type: Video doesn't play

Steps to Reproduce
Give more details

1. Navigate to: www.foxnews.com
2. Navigate to the Video section and tap on any video available.

Expected Behavior:
The video is played.

Actual Behavior:
The video is not played. An error is displayed: "Error: Source not supported."

Notes:

1. The issue is also reproducible on the Firefox 52.0 Release.
2. The issue is not reproducible on Chrome (Mobile) 56.0.2924.87.

sv; country: us

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