Adding a sensor now has 3 filters: select all / Select all disconnected / Deselect all Interfaces.
But iIf you have a device, e.g. a switch with hunderds of interfaces and you'd like to add some new interfaces to it; You'll have to figure out what is already being monitord before adding more. Else you'll have double sensors.
It would be nice to have a checkmark to only show not-exising sensors. That way there are never unnecessary doubles and autodiscovery can be avoided.