diff --git a/main.js b/main.js
index 91f2530..837bc7b 100644
--- a/main.js
+++ b/main.js
@@ -5,6 +5,7 @@ const os = require('os');
 const log = require('electron-log/main');
 const { linkExists } = require('link-exists');
 const { setInterval } = require('node:timers/promises');
+const { type } = require('node:os');
 
 
 //------------------------------------------------------------------------------
@@ -80,24 +81,32 @@ async function createWindow() {
         autoHideMenuBar: true
     });
 
-    win.on("closed", function () {
-        win = null;
+    // register event callbacks
+    win.on("closed", function () { win = null; });
+    win.webContents.on("will-frame-navigate", (event) => validateDomain(event));
+    win.webContents.setWindowOpenHandler(({ url }) => {
+        // we need to manually validate the url as `loadURL` 
+        // doesn’t trigger the `will-navigate` event
+        let event = new Event("DummyNavigation");
+        event.url = url;
+        if (validateDomain(event)) {
+            win.loadURL(url);
+        }
+        return { action: 'deny' };
     });
 
-    win.webContents.addListener("will-navigate", validateDomain);
+    // show black window
+    // win.setKiosk(true);
+    win.show();
 
-    win.once("ready-to-show", () => {
-        win.setKiosk(true);
-        win.show();
-    });
-
-    // load fallback page
-    win.loadFile('index.html');
 
     // load actual page from config file
     if (config != undefined && 'url' in config) {
         testAndLoadUrl(config.url);
     }
+
+    // load fallback page
+    // win.loadFile('index.html');
 }
 
 /**
@@ -106,11 +115,18 @@ async function createWindow() {
  * @param {Event} event 
  */
 function validateDomain(event) {
+    console.log(event.type);
+    if (config == undefined) return;
+
     let url = new URL(event.url);
+
     if ('allowedDomains' in config && !config.allowedDomains.includes(url.hostname)) {
         event.preventDefault();
         log.info("Navigation to " + event.url + " prevented");
+        return false;
     }
+
+    return true;
 }
 
 /**