Well it is actually a valid IP address but it's a link local one, so equivalent to 192.168.???.???(*). So for a utility like the BQM fe80 is rejected since there is no way devices outside your LAN can ping it.
The BQM checker agrees with you.
I have the address beginning with fe80::
and it is throwing up stating it's not a valid IP address so will not let me create a BQM over IPv6
IPv6 is a funny thing though. I just checked this laptop and it currently has six global IP addresses, one is preferred, the other five are temporary and deprecated. It also has a link-local address.
(*)Or that portion of that range which is private anyway.
Edited by Andrue (Sat 05-Dec-20 09:03:59)