the Rendering Progress Bar

this is a tiny little request, nothing much at all, but it's happened a couple of times that i dont know if an effect has rendered yet or not. that might seem odd and maybe it is, but nonetheless, i'd like a way to tell via the rendering progress bar whether the render has started or already run. maybe the field with the bar in it could turn a different color or something. i dont know; but because sometimes a render can take a fair amount of time to start and sometimes the render can go so fast, if you blinked you didnt see it, that i'd like to know for sure. i wouldnt like a popup saying it occurred. too many of those get annoying. but maybe just a color change or something?