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Firefox hangs play of HTML5 <VIDEO> element, keeps using near 100% CPU after closing the tab, fails to restart.

  • 1 reply
  • 1 has this problem
  • 7 views
  • Last reply by zikzak

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1) Visit this URL, let it play for 22 seconds, listen to your laptop/desktop CPU fan start screaming.

Espected behavior: the video should loop. Actual behaviour: the video hangs just before the end and CPU usage goes to maximum

2) While the video is hung, close the tab.

Expected behaviour: the tab and all its resources should be freed, which should stop the high CPU usage. Actual behaviour: the tab closes but CPU usage remains at maximum.

3) Shut down the browser and restart.

Expected behaviour: The browser should close, and then the browser should start when clicking the app icon again. Actual behaviour: Firefox closes the window but remains at max CPU usage indefinitely. Firefox is unable to restart.

Here's the URL which causes the problems listed above: http://ukcom.org/l/h/miwflow330px.html

1) Visit this URL, let it play for 22 seconds, listen to your laptop/desktop CPU fan start screaming. Espected behavior: the video should loop. Actual behaviour: the video hangs just before the end and CPU usage goes to maximum 2) While the video is hung, close the tab. Expected behaviour: the tab and all its resources should be freed, which should stop the high CPU usage. Actual behaviour: the tab closes but CPU usage remains at maximum. 3) Shut down the browser and restart. Expected behaviour: The browser should close, and then the browser should start when clicking the app icon again. Actual behaviour: Firefox closes the window but remains at max CPU usage indefinitely. Firefox is unable to restart. Here's the URL which causes the problems listed above: http://ukcom.org/l/h/miwflow330px.html

Modified by linuxgeex

All Replies (1)

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No issue for me, after 4 loops my CPU load was around 18%. Firefox 33.1.1 under Windows Vista.