What's This "NO" Symbol With Arrows?

When I try to run a macro that activates Finder, if Finder has no windows open and "Reopen initial windows" is unchecked, I get this symbol briefly on the screen:

What does it mean? Is it coming from Keyboard Maestro or the System?


Hey Russell,

This critter?


That's Moom – not the system or Keyboard Maestro.


Hey, I know that symbol ;). And yea, it's Moom telling you you're trying to either interact with a window that can't be interacted with (resizing System Preferences, for instance), or that it can't find a window that it can work with.