I wonder if the circle or rectangles are filled/stroked with a white paint? You could go to View > Display Mode > Outline which will show you the circle or square without any stroke/fill. Alternatively select the handles and then change the stroke/fill.
Beyond the Basics creat geometrics
Inkscape.org
cannot create circle or rectangle but can create 3D. Only shows handles
I wonder if the circle or rectangles are filled/stroked with a white paint? You could go to View > Display Mode > Outline which will show you the circle or square without any stroke/fill. Alternatively select the handles and then change the stroke/fill.