avahi-autoipd.action and avahi-dnsconfd.action should be added to the backup array for the PKGBUILD since those files, albeit seldomly edited, are available for the user to edit to customize the action script on avahi SLAAC and mdns. In my case which I do edit them I find frustratingly having to restore them from backup everytime there's an update. Since they are meant for the user to edit them rather than internal machinery, there's no reason not to have them in backup.