widen the area to activate a layer in the layer window for use with the mouse

[katpatuka]

Using the mouse it's a bit difficult to switch to another layer in the Layer Window because the area where the mouse can activate another layer seems to be very small: only the left-side edge is sensible to the mouse.

See screenshot: switching to layer Fujian.osm is not possible in the upper screenshot where the text reads this layer has no native resolution; the cursor has to be moved left exactly under the green icon to be able to activate that layer.