Warn if a label relates to exactly 1 node

I changed the relative postions (and labels) of various supply rails when updating a project. I found a logical mistake (my fault) only after soldering the PCB. The problem was that one resistor connected to a single-node net "Vss".

So, one resistor has a pad which connects to nothing else.

Of course, "Vss" was a supply rail label which existed in the old project. It should not have existed in the new project.

I checked again. At netlist import, Kicad does actually report the situation -
   "Remove single pad net "Vss" on "R44" pad '2' "
but does not highlight it as a warning.

I wonder if this situation should be upgraded to a warning? Maybe also the warning would be better at net export time - a clickable list of warnings & errors.