.localhost will be dropped as DHCP search domain by systemd-networkd, see <a href="https:&#x2F;&#x2F;github.com&#x2F;systemd&#x2F;systemd&#x2F;issues&#x2F;2258" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;systemd&#x2F;systemd&#x2F;issues&#x2F;2258</a><p>Not sure if that is important for the use-case at hand, but it was the reason why I stopped using .localhost in my LAN (in favor of just using plain hostnames, e.g. “x1”).