How do you stop drawing polylines?
Some softwares use a right click to mean the end the polyline and the dangling segment is discarded. Google docs use the addition of a point very close to the last point. Other softwares use the Escape key. For the curve editor in Blender I always have to check the documentation.
How do you end a polyline in Google Docs?
Place the line on your drawing: Line, Elbow Connector, Curved Connector or Arrow: Click to start, then drag across the canvas. Curve or Polyline: Click to start, then click at each point you want the line to bend. Double-click or complete the shape to finish.