Router WAN port has internal VLANS and LAN devices showing, bug?

Router is running 1.3l

Just noticed that the WAN port on my router 10 shows the port with Internal VLANS, surely thats a bug? W1 is Untagged VLAN1, TAgged VLAN 15,20?



The WAN is port showing internal device connected to it, when they should be connected to the LAN port(s)

Would expect the ONT as connected to that port.