fix: factory ext

src/lib/factory.ts

@@ -88,7 +88,7 @@ export class DomainFactory {
   newDomain(domain: string): Domain {
     return {
       name: domain,
-      extension: domain.split(".", 1)[1] ?? "",
+      extension: domain.split(".").slice(1).join("."),
       searching: false,
       available: true,
     };