- A domain's name in any list opens a card on hover: whether it's taking
mail, how many people it has, which of its key records (mail routing,
SPF, DKIM, DMARC) are live in public DNS, and whether DNS, signing keys
and certificates are automatic.
- A person's shows their name, storage against their quota, role, groups
and when they joined. The server keeps no last sign-in on the account,
so the card doesn't claim one.
- Cards load on open and are cached for a minute.
- Option tooltips end with the option's default, and an option set away
from its default gets a small "changed" mark.