[Playlist] New "valid XSPF" button proposal

[Lucas Gonze]

>> - Have you tried a reversed color scheme to see how it works with other
>> backgrounds?
>
> -----------------------------------------------------------
> No. I didn't even think about it. Shouldn't it work
> on any background if the border is dark and the main color
> light? Yes, there is a lazy component in this answer ;-)

If the source for the button was available, would third parties who need 
a bigger/ smaller/ reversed version make the edits and contribute them 
back, or would they just not use any button at all?