First, select a geometry which vertexes will be inserted, moved or removed. When activating the tool it will be showed all vertexes belonging to selected geometry making possible to choose the vertex that will be affected by the operation.
Click on the icon
+ mouse double click over a polygon side to insert vertexes in lines
or polygons and click where the vertex is to be inserted.
Click on the icon
+ shift key + click with mouse left button to delete vertexes in
lines or polygons and click on the vertex to be removed. As a result,
the vertexes sequence is updated, i.e., the previous vertex and next
vertex from the removed one become consecutive and therefore joined
by a line.
Click on the icon
to move any vertex to other place. This procedure updates dynamically
the selected geometry containing the vertex. Observe the vertex
sequence is not changed, previous and next vertexes to the moved one
continue in same position.
Click on the icon
to save the change.