Widget description
In the lower left corner of the map window, you will see the corresponding Contour lines icon. To use the widget you need to:

1. Click on the “Contour lines” icon
2. Select the desired step of the Contour lines
3. Click the Choose extent button
4. Draw an extent on the map
5. Click the Get button

Next, the user can save the obtained Contour lines to data sources and automatically add them to the list of layers (see figure 2).

Video tutorial