Whether to enable IPv6 Privacy Extensions for interfaces not configured explicitly in networking.interfaces.<name>.tempAddress. This sets the ipv6.conf.*.use_tempaddr sysctl for all interfaces. Possible values are: "default" to generate IPv6 temporary addresses and use these as source addresses in routing; "disabled" to completely disable IPv6 temporary addresses; "enabled" to generate IPv6 temporary addresses but still use EUI-64 addresses as source addresses;

if ${config.networking.enableIPv6} then "default" else "disabled"