How to check if a SOLIDWORKS Face is Planar / Flat

How can you check for a SOLIDWORKS Planar Face with one mouse click? Just select a face in the graphic area and see if the Insert Sketch icon appears in the shortcut selection menu (fig. 1).

Fig 1: Insert Sketch button

If the shortcut menu appears with the Insert Sketch button available, the face is planar (fig. 2).

Fig 2: Face is Planar

If you do not see the Insert Sketch icon, the surface is not planar (fig. 3)

Fig 3: Face is NOT Planar