[BUG/Interface] Can't scroll the map if no unit was selected +Scroll left only works in the top left corner

Bug description : If a unit was selected when moving the mouse cursor to the edges of the screen the maps scroll's in that direction , when no unit was selected  then the map doesn't scroll/Even when a unit selected scrolling to the left can ,most of the time, only be done by moving the cursor to the top left corner

Steps to repreduce :

1)Clear slection ( by left clicking on an empty space on the map) 

2)Move the mouse cursor to one of the screen edges.

If it help I can put up a video of the problem

Anyway hope this helps