Under "Network" PiHole display the MAC address for every device it found.
Now it would be a lot more easy if we can use the MAC address in group management for adding new clients too.
Reason:
If network use IPv6, PiHole list every one (correctly) in the "Network" overview but also under management too which create a long list and create problems if only the IPv4 address is added.
Using the MAC address from a device would solve that and is more persistent as IPv4 and IPv6