How can I turn off the screen blackout in Linux when playing a film in BBC iPlayer? I usually use it in Chrome, but if there is a way to do it in Firefox (Iceweasel) than it is good enough as well.
I think by default iPlayer uses Flash, but if there is a way to switch to HTML 5 that does the job than I am fine to do it as well.
I know how to turn it off completely, but obviously I want it to save energy in all other circumstances.