PortShifting | Node table

GoJS
4

I found the solution:

I changed the Panel from vertical to Spot then I added a new panel with spot / Rectangle to manage port space :

 $(go.Panel, "Spot",
                $(go.Panel, "Spot",
                    $(go.Shape, "Rectangle", {stroke: null, width:0,background: "transparent", fill: null})
                 ),

this post helped me : POST

thanks!