Requested feature/update:
If I left click on the map where there is no marker/icon, I want the game to do nothing.
Explanation:
You can already get a context menu from right-click. And we are all used to right-clicking for a context menu. Further if you pan the map (move it around), you might sometimes accidentally pan a very short distance or not pan at all, and then you accidentally get a waypoint context menu.
One button assignment for this is enough and the distinction between
Left click - panning (dragging)
Right click - way point menu
is intuitive and less error prone.