Option to add IPv6 addresses to bridge interface

[sfx2000]

Are you sure you don't already have an IPv6 address? I've just looked at my old RT-AC68U and with IPv6 enabled but the WAN down it has a link local address (EUI-64).

Concur - and even when the WAN link is up, one likely should see both routable and link-local address assigned to the interfaces, and if I recall, even the bridge interface...