Thanks for the reply but that's not quite what I was asking, the current feature chanegs the opacity of ICONS AND fence Background.
I'm asking for the ability to change the opacity of the fence BACKGROUND while leaving the icon opacity untouched; or vice-versa for that matter.
Come to think of it, it might be good alternative to quick-hide on desktop empty area double click:
Double click empty desktop area to toggle semi-opaque<-> full opaque fences (background and/or icons).