To reproduce:
- Start MITK and load any image
- Right-click on the loaded image and select "Show only selected nodes" in the context-menu
- See how the crosshair is disabled by hiding the plane-nodes
This is even more annoying if the plane-nodes are not shown in the data manager (helper objects not shown). In this case one can not immediately enable the planes again, since there is no context-menu entry like "Show all nodes".