Arrow keys could override the mouse scrolling?

[Jequ]

I find it annoying that if your cursor isn't on the Wesnoth window, it is impossible to move around in the map with the arrow keys. I use a laptop so I can't easily use the mouse at the same time to move it on the window. This feature won't even influence player who prefer mouse scrolling so it is all good.

And I think it is (I am not sure, though...) quite trivial fix so a less experienced coder can implement it, for practise.

[Soliton]

Toggle the "Keep scrolling when mouse leaves the window" advanced preference.