Icon for Medium on the Area (Main Line) should differ between different media (like it is already done for the Line)

It seems as if the Icon for the Area (Main Line) does not change, no matter what "Main Line Medium" is selected.

It always looks like this:

If the medium type for the Line is change, the Icon gets changed accordingly:

TP1: 

PL: 

RF: 

IP: 

It would be grat if the Icon of the Main Line would also change, this would make the topology tree view more transparent to the user.

Best Regards,

Christian Winnewisser