See, I already have an image there:
<--- all 4 states
....if I color one of the images ('normal' in this example) red, this is what I get:
You are using a light theme, so maybe the white outline isn't as obvious.
Same thing in MrGrim's 'Blade for 8.1' theme:
...so I guess it's normal/unchange-able in 8.1? Or perhaps editing some code in shellstyle fixes it? Oh well, it's not a big deal and I don't want to fiddle with the shellstyle tonight.
Thanks again for your help, my friend.