diff --git a/ext/fg/js/frontend-api-sender.js b/ext/fg/js/frontend-api-sender.js
index 93c2e593..8dc6aaf3 100644
--- a/ext/fg/js/frontend-api-sender.js
+++ b/ext/fg/js/frontend-api-sender.js
@@ -19,7 +19,7 @@
 
 class FrontendApiSender {
     constructor() {
-        this.senderId = FrontendApiSender.generateId(16);
+        this.senderId = yomichan.generateId(16);
         this.ackTimeout = 3000; // 3 seconds
         this.responseTimeout = 10000; // 10 seconds
         this.callbacks = new Map();
@@ -123,12 +123,4 @@ class FrontendApiSender {
         info.timer = null;
         info.reject(new Error(reason));
     }
-
-    static generateId(length) {
-        let id = '';
-        for (let i = 0; i < length; ++i) {
-            id += Math.floor(Math.random() * 256).toString(16).padStart(2, '0');
-        }
-        return id;
-    }
 }
diff --git a/ext/mixed/js/core.js b/ext/mixed/js/core.js
index 2dd9cf40..b6ecb48b 100644
--- a/ext/mixed/js/core.js
+++ b/ext/mixed/js/core.js
@@ -257,6 +257,16 @@ const yomichan = (() => {
 
         // Public
 
+        generateId(length) {
+            const array = new Uint8Array(length);
+            window.crypto.getRandomValues(array);
+            let id = '';
+            for (const value of array) {
+                id += value.toString(16).padStart(2, '0');
+            }
+            return id;
+        }
+
         triggerOrphaned(error) {
             this.trigger('orphaned', {error});
         }