Comment 1 for bug 1068576

In my opinion this should be fixed independently of the webapps

Is this html5 videos? Flash videos or both?
For flash you can always use caffeine (which should be in the default distribution imo) and for html5 I already filed a bug:
https://bugs.launchpad.net/ubuntu/+source/firefox-3.5/+bug/434476

I think flash videos will be gone soon (at least for youtube) so we should focus on html5.