If I want to draw some vertices on the ground plane, I seem to have to place the first vertex with Ctrl+RMB (not Ctrl+LMB as the manual states), then Extrude the rest of the vertices using E, which is fine, except that using Ctrl+RMB seems to ignore my snap to grid settings (using E behaves properly), so I can't accurately place that first vertex.

Is there a way of making that snap when it's placed, rather than having to move it afterwards using Blender 2.8?