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Why can't I watch video ?

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I'm using FF 43.0.1 on Windows.

Before I upgraded, videos played without any problem.

Now, when trying to play the top video on this page https://twitter.com/TwitterTips/timelines/581843572464443392 ,

I get the message "This browser does not support video playback."

What's gone wrong ?

How do I resolve the issue, please ?

I'm using FF 43.0.1 on Windows. Before I upgraded, videos played without any problem. Now, when trying to play the top video on this page https://twitter.com/TwitterTips/timelines/581843572464443392 , I get the message "This browser does not support video playback." What's gone wrong ? How do I resolve the issue, please ?

All Replies (2)

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Please also update the video extensions in your browser:

If you see any issues also see:

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You are probably out of luck with being on Windows XP. XP doesn't support playing MP4 files natively, so Firefox isn't able to play MP4 files via the HTML5 media player.