Targetting none?

[Niwashi]

Increasing the size of the minimap doesn't increase the ammount of terrain displayed

You can zoom in and out on the minimap from the + and - buttons on its right edge. That helps somewhat, though it only has a few zoom levels, so doesn't give as much flexibility in that regard as the main map window has.

I agree that there certainly should be a simple way to just remove your target focus without closing windows in the process.