- New CSV format with port, for example `ip1:port1,ip2:port2`
- retrocompatibility with `DNS_ADDRESS`. If set, force upstream type to plain and empty user-picked providers. 127.0.0.1 is now ignored since it's always set to this value internally.
- requires `DNS_UPSTREAM_TYPE=plain` must be set to use `DNS_UPSTREAM_PLAIN_ADDRESSES` (unless using retro `DNS_ADDRESS`)
- Warning log on using private upstream resolvers updated
