diff --git a/Build/lib/writing-strategy/singbox.ts b/Build/lib/writing-strategy/singbox.ts
index 73874b2a..52863d7c 100644
--- a/Build/lib/writing-strategy/singbox.ts
+++ b/Build/lib/writing-strategy/singbox.ts
@@ -53,7 +53,7 @@ export class SingboxSource extends BaseWriteStrategy {
   }
 
   writeDomainSuffix(domain: string): void {
-    (this.singbox.domain_suffix ??= []).push(domain);
+    this.singbox.domain_suffix.push(domain);
   }
 
   writeDomainKeywords(keyword: Set<string>): void {