OSPFv3 doesn't announce loopback IPv6 network

[Bernd Naumann]

On 11.12.22 18:50, Ondrej Zajicek via Bird-users wrote:
> On Sun, Dec 11, 2022 at 06:30:46PM +0100, Bernhard Ehlers via Bird-users wrote:
>> I want to use OSPF with BIRD v2.0.10 on Linux.
>>
>> That works well, except that the IPv6 network of the lo interface isn't
>> announced on OSPFv3. The IPv6 networks of the ethernet interfaces are
>> announced as well as the IPv4 networks of all interfaces (ethernet and lo).
>> The only missing is the IPv6 network of lo.
> 
> Hi
> 
> Due to some implementation details, OSPFv3 ignores interfaces that do not
> have link-local addresses (even if they are just stub). Just use:
> 
> ip address add fe80::1/128 dev lo
> 

May I ask why not using the direct protocol to get the loopback addresses?