twitter.com - repeatedly clicking a video makes it change to "The media could not be played"

[dholbert]

URL: https://twitter.com/ChemistryReacts/status/802988596231897089
Browser / Version: Firefox 53.0
Operating System: Linux
Problem type: Unknown

Steps to Reproduce

1. Navigate to: https://twitter.com/ChemistryReacts/status/802988596231897089
2. When the play button appears, click it.
3. After the video starts, click the video (or its play/pause button) over and over.

Expected Behavior:
Video pauses/plays over and over.

Actual Behavior:
Video pauses/plays a few times, and then suddenly it changes to a black "The media could not be played."

This is a website bug that seems to happen cross-browser -- I'm hitting it in Firefox 53 Nightly, Firefox 50 (release), and Chrome 55 dev-edition. (All on Linux)

Here's a screenshot of the video after it breaks:

If it matters, I'm on Starbucks WiFi right now. (e.g. it's possible this only happens on rate-limited connections; not sure though)

From webcompat.com with ❤️

[dholbert]

(Not sure if there's a better way to reach Twitter developers, but I tweeted at their support account .)

[tsl143]

Just to mention, this happens both on Firefox as well as Chrome.

[magsout]

@dholbert @tsl143 I can't reproduced on Mac, OS, is it a LInux issue ?

[dholbert]

Seems to be platform-independent to me. (I reported from Linux, but I just tested & easily reproduced in Firefox 52 DevEdition on MacOS Sierra, and in Chrome 55 on Windows 10 -- using BrowserStack to test those other OSes with clean environments.)

Maybe you're not clicking the video aggressively enough? :)

[wisniewskit]

I can reproduce this, but it only happens on some videos: the one provided, the one for Jan 15 with the bridge being demolished, the "And they told me electromagnetism wasn't magic" one, the ballon-popping one, and that's as far down as I tried. The rest of the ones along the way are working fine. I can right-click to reload the frames for the failed ones to re-watch them.

The same videos fail for me in Chrome and Firefox, in Gentoo Linux and OSX 10.11, and also Edge in the VirtualBox VM downloadable from Microsoft.

Curiously, the issue does not happen in Safari on the same MacBook I tested Firefox and Chrome in. I can't quite tell why this is the case, but when I look at the network logs while pausing/resuming, Firefox and Chrome keep re-requesting the mpeg2 ts stream, while Safari does not (though I suppose it's possible that Safari could be re-requesting it each time and not showing it in their network log; I haven't sniffed the traffic).

[wisniewskit]

The fix for this has just landed in bug 1335098. The videos are now pausing/unpausing correctly for me in today's nightly.

[dholbert]

Great! Confirmed -- I can't reproduce anymore in Nightly or in Chrome.

(Also: to clarify, bug 1335098 is classified as a Tech Evang bug, and the fix that landed there was on Twitter's end. Makes sense, given prior comments here.)