[Trisquel-users] Force different aspect ratio in secondary screen (or in Firefox?)

[gnuser]

Hello everyone!

So, my T400 is connected to my TV using VGA. I can only use 1024x768 (other  
resolutions don't look properly on the TV) which is a 4:3 AR but the TV is  
actually shaped as 16:9 screen. So, when I get some video to play there I get  
the image "horizontally stretched", everything seems a dwarf version of what  
is should. Playing movies in VLC is not a problem because VLC adjusts the  
image for the proper AR on demand. However if I try to watch a video online  
using html5 I have no way to change the AR and so even if the video is 16:9  
it still gets the black bars on top and the bottom. Any idea how to change  
it?

Thanks.