One could also put the map into the background; one may just need to test that when having multiple monitors :) But since FGU does not restrict oneself just to the boundary of the image, one can adjust the zoom etc. such that the map just shows on one monitor (while the others have then the black/gray background or the non-focused parts of the map) :) But different resolutions of the monitors could result into a cut-out toolbar or so, so, I'd test first :)