diff --git a/scripts/background/task.js b/scripts/background/task.js
index 2b61195..fab8302 100644
--- a/scripts/background/task.js
+++ b/scripts/background/task.js
@@ -42,6 +42,7 @@ class Task {
     }
     clean() {
         this._data = {};
+        this._data_keys = [];
     }
     async execute(tab, upstreamData) {
         if (!tab) return Promise.reject("No tab to execute the task.");