Hii,
I noticed that the ipaddr filter seems to compress IPv6 addresses.
For example I feed a list to ipaddr that contains (among other things)
uncompressed IPv6 addresses:
To answer my own question, it seems there is: ipv6form.
The docs are mangled though:
https://docs.ansible.com/ansible/latest/collections/ansible/utils/ipv6form_filter.html
I was able to get what I need by reading the source.
Dick