Currently when one goes into Clear Physics mode in the NL editor, the background does not change to black. If using Clear Physics mode while playing a level the background does turn black. Maybe the same should be true when creating a level in the editor as the background can be distracting while making a level at times.
Maybe a check box that can toggle it?
There's already a hotkey (F6), which is more convenient than a checkbox. I agree, though, that making this an automatic part of Clear Physics mode so you don't have to press two keys (F1, F6) would be an improvement on the current situation.
I am also in favor of this. :)
Done.