Hello,
it seems that assigning an address of
::/64
to an ether interface makes Winbox not discover the device anymore. Manual connection via IP or MAC is possible though. If I use
::1/64
it works like a charm. Some documentation had the former sample, and you can end up with this if DHCPv6 client is not running properly. Discovered this on 6.37 or 6.38, and also 6.40.3 has that effect. Not sure it’s a bug though.
It does not seem to matter whether that entry is enabled or disabled, as long as it exists.