diff --git a/src/setup/config.ts b/src/setup/config.ts
index 88705e24..2e1634a4 100644
--- a/src/setup/config.ts
+++ b/src/setup/config.ts
@@ -95,6 +95,6 @@ export function conf(): RuntimeConfig {
           .map((s) => s.trim())
           .filter((s) => s.length > 0),
       )
-      .filter((v) => v.length > 0), // The format is <beforeA>:<afterA>,<beforeB>:<afterB>
+      .filter((v) => v.length === 2), // The format is <beforeA>:<afterA>,<beforeB>:<afterB>
   };
 }