diff --git a/app/src/main/java/io/legado/app/help/JsExtensions.kt b/app/src/main/java/io/legado/app/help/JsExtensions.kt
index 971f580e9..fc2fc92ff 100644
--- a/app/src/main/java/io/legado/app/help/JsExtensions.kt
+++ b/app/src/main/java/io/legado/app/help/JsExtensions.kt
@@ -66,7 +66,7 @@ interface JsExtensions {
         FileUtils.deleteFile(zipPath)
         val zipFile = FileUtils.createFileIfNotExist(zipPath)
         StringUtils.hexStringToByte(content).let {
-            if (it != null) {
+            if (it.isNotEmpty()) {
                 zipFile.writeBytes(it)
             }
         }