diff --git a/.changelog/pr-2329.txt b/.changelog/pr-2329.txt
new file mode 100644
index 00000000..863d29a2
--- /dev/null
+++ b/.changelog/pr-2329.txt
@@ -0,0 +1 @@
+Fix: Ensure all notification methods return a Notification-like stub for Teams. - by @IsmaelMartinez (#2329)
diff --git a/app/browser/preload.js b/app/browser/preload.js
index 5788a46b..f2ea142e 100644
--- a/app/browser/preload.js
+++ b/app/browser/preload.js
@@ -151,6 +151,35 @@ ipcRenderer.invoke("get-config").then((config) => {
   console.error("Preload: Failed to load config for notifications:", err);
 });
 
+// Create a Notification-like stub so Teams can manage lifecycle without errors.
+// Without addEventListener/close/dispatchEvent, Teams' internal state machine
+// breaks after the first notification, causing subsequent ones to stop firing.
+function createNotificationStub() {
+  const stub = {
+    onclick: null,
+    onclose: null,
+    onerror: null,
+    onshow: null,
+    close() { if (this.onclose) this.onclose(); },
+    addEventListener(type, listener) {
+      if (type === 'click') this.onclick = listener;
+      else if (type === 'close') this.onclose = listener;
+      else if (type === 'show') this.onshow = listener;
+      else if (type === 'error') this.onerror = listener;
+    },
+    removeEventListener(type, listener) {
+      if (type === 'click' && (!listener || this.onclick === listener)) this.onclick = null;
+      else if (type === 'close' && (!listener || this.onclose === listener)) this.onclose = null;
+      else if (type === 'show' && (!listener || this.onshow === listener)) this.onshow = null;
+      else if (type === 'error' && (!listener || this.onerror === listener)) this.onerror = null;
+    },
+    dispatchEvent() { return true; },
+  };
+  // Fire the show event asynchronously like a real Notification
+  setTimeout(() => { if (stub.onshow) stub.onshow(); }, 0);
+  return stub;
+}
+
 // Helper functions for notification handling (extracted to reduce cognitive complexity)
 function playNotificationSound(notifSound) {
   if (globalThis.electronAPI?.playNotificationSound) {
@@ -195,8 +224,7 @@ function createElectronNotification(options) {
       console.debug("showNotification failed", e);
     }
   }
-  // Return stub object for Electron notifications
-  return { onclick: null, onclose: null, onerror: null };
+  return createNotificationStub();
 }
 
 function createCustomNotification(title, options) {
@@ -229,8 +257,7 @@ function createCustomNotification(title, options) {
     console.error("Failed to send custom notification:", e);
   }
 
-  // Return stub object
-  return { onclick: null, onclose: null, onerror: null };
+  return createNotificationStub();
 }
 
 // Override window.Notification immediately before Teams loads
diff --git a/tests/e2e/notifications.spec.js b/tests/e2e/notifications.spec.js
new file mode 100644
index 00000000..c99eee17
--- /dev/null
+++ b/tests/e2e/notifications.spec.js
@@ -0,0 +1,340 @@
+import { test, expect } from '@playwright/test';
+import { _electron as electron } from 'playwright';
+import { mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+
+/**
+ * Notification lifecycle tests.
+ *
+ * Verifies that the preload.js Notification override returns objects with
+ * the lifecycle methods Teams expects (addEventListener, removeEventListener,
+ * close, dispatchEvent). Without these, Teams' internal state machine breaks
+ * after the first notification call, causing subsequent ones to silently fail.
+ *
+ * These tests launch the app with a clean profile (no login session), so they
+ * exercise the preload in a real Electron renderer without needing Microsoft
+ * authentication. They work both locally and inside Docker cross-distro
+ * containers.
+ */
+
+const LIFECYCLE_METHODS = ['addEventListener', 'removeEventListener', 'close', 'dispatchEvent'];
+const CALLBACK_PROPERTIES = ['onclick', 'onclose', 'onerror', 'onshow'];
+
+async function launchApp(notificationMethod) {
+  const userDataDir = mkdtempSync(join(tmpdir(), 'teams-e2e-notif-'));
+  const args = [
+    './app/index.js',
+    `--notificationMethod=${notificationMethod}`,
+    ...(process.env.CI ? ['--no-sandbox'] : []),
+  ];
+
+  const electronApp = await electron.launch({
+    args,
+    env: { ...process.env, E2E_USER_DATA_DIR: userDataDir },
+    timeout: 30000,
+  });
+
+  return { electronApp, userDataDir };
+}
+
+async function getMainWindow(electronApp) {
+  await electronApp.firstWindow({ timeout: 30000 });
+  // Wait for windows to settle
+  await new Promise(resolve => setTimeout(resolve, 4000));
+
+  const windows = electronApp.windows();
+  // Find a window with a real page (not about:blank)
+  return windows.find(w => {
+    const url = w.url();
+    try {
+      const hostname = new URL(url).hostname;
+      return hostname === 'teams.cloud.microsoft' ||
+        hostname === 'teams.microsoft.com' ||
+        hostname === 'teams.live.com' ||
+        hostname === 'login.microsoftonline.com';
+    } catch {
+      return false;
+    }
+  });
+}
+
+async function cleanup(electronApp, userDataDir) {
+  if (electronApp) {
+    try {
+      await Promise.race([
+        electronApp.close(),
+        new Promise((_, reject) => setTimeout(() => reject(new Error('timeout')), 5000)),
+      ]);
+    } catch {
+      try {
+        const pid = electronApp.process()?.pid;
+        if (pid) process.kill(pid, 'SIGKILL');
+      } catch { /* ignore */ }
+    }
+  }
+  if (userDataDir) {
+    try { rmSync(userDataDir, { recursive: true, force: true }); } catch { /* ignore */ }
+  }
+}
+
+test.describe('Notification override', () => {
+  test('window.Notification is overridden with correct static API', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      // Check static API
+      const permissionValue = await mainWindow.evaluate(() => window.Notification.permission);
+      expect(permissionValue).toBe('granted');
+
+      const requestResult = await mainWindow.evaluate(() => window.Notification.requestPermission());
+      expect(requestResult).toBe('granted');
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('electron method returns stub with lifecycle methods', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      // Create a notification and inspect the returned object
+      const stubShape = await mainWindow.evaluate(() => {
+        const n = new window.Notification('Test', { body: 'test body' });
+        return {
+          hasAddEventListener: typeof n.addEventListener === 'function',
+          hasRemoveEventListener: typeof n.removeEventListener === 'function',
+          hasClose: typeof n.close === 'function',
+          hasDispatchEvent: typeof n.dispatchEvent === 'function',
+          hasOnclick: 'onclick' in n,
+          hasOnclose: 'onclose' in n,
+          hasOnerror: 'onerror' in n,
+          hasOnshow: 'onshow' in n,
+        };
+      });
+
+      expect(stubShape.hasAddEventListener).toBe(true);
+      expect(stubShape.hasRemoveEventListener).toBe(true);
+      expect(stubShape.hasClose).toBe(true);
+      expect(stubShape.hasDispatchEvent).toBe(true);
+      expect(stubShape.hasOnclick).toBe(true);
+      expect(stubShape.hasOnclose).toBe(true);
+      expect(stubShape.hasOnerror).toBe(true);
+      expect(stubShape.hasOnshow).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('electron stub addEventListener wires up callbacks correctly', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      const result = await mainWindow.evaluate(() => {
+        const n = new window.Notification('Test', { body: 'test' });
+        let clickFired = false;
+        let closeFired = false;
+
+        n.addEventListener('click', () => { clickFired = true; });
+        n.addEventListener('close', () => { closeFired = true; });
+
+        // Simulate Teams calling onclick/onclose
+        if (n.onclick) n.onclick();
+        if (n.onclose) n.onclose();
+
+        return { clickFired, closeFired };
+      });
+
+      expect(result.clickFired).toBe(true);
+      expect(result.closeFired).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('electron stub removeEventListener clears callbacks', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      const result = await mainWindow.evaluate(() => {
+        const n = new window.Notification('Test', { body: 'test' });
+        const handler = () => {};
+
+        n.addEventListener('click', handler);
+        const hadHandler = n.onclick === handler;
+
+        n.removeEventListener('click', handler);
+        const cleared = n.onclick === null;
+
+        return { hadHandler, cleared };
+      });
+
+      expect(result.hadHandler).toBe(true);
+      expect(result.cleared).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('electron stub close() triggers onclose callback', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      const closeFired = await mainWindow.evaluate(() => {
+        const n = new window.Notification('Test', { body: 'test' });
+        let fired = false;
+        n.addEventListener('close', () => { fired = true; });
+        n.close();
+        return fired;
+      });
+
+      expect(closeFired).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('electron stub fires show event asynchronously', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      const showFired = await mainWindow.evaluate(async () => {
+        const n = new window.Notification('Test', { body: 'test' });
+        let fired = false;
+        n.addEventListener('show', () => { fired = true; });
+        // Wait for the async setTimeout(0) to fire
+        await new Promise(resolve => setTimeout(resolve, 50));
+        return fired;
+      });
+
+      expect(showFired).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('custom method returns stub with lifecycle methods', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('custom'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      const stubShape = await mainWindow.evaluate(() => {
+        const n = new window.Notification('Test', { body: 'test body' });
+        return {
+          hasAddEventListener: typeof n.addEventListener === 'function',
+          hasRemoveEventListener: typeof n.removeEventListener === 'function',
+          hasClose: typeof n.close === 'function',
+          hasDispatchEvent: typeof n.dispatchEvent === 'function',
+        };
+      });
+
+      expect(stubShape.hasAddEventListener).toBe(true);
+      expect(stubShape.hasRemoveEventListener).toBe(true);
+      expect(stubShape.hasClose).toBe(true);
+      expect(stubShape.hasDispatchEvent).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('web method does not break native Notification lifecycle', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('web'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      // For web method, verify the override exists and returns something
+      // (either a real Notification or a bare fallback). The key assertion is
+      // that calling new Notification() does not throw.
+      const result = await mainWindow.evaluate(() => {
+        try {
+          const n = new window.Notification('Test', { body: 'test body' });
+          return {
+            didNotThrow: true,
+            type: typeof n,
+            hasOnclick: 'onclick' in n,
+          };
+        } catch (e) {
+          return { didNotThrow: false, error: e.message };
+        }
+      });
+
+      expect(result.didNotThrow).toBe(true);
+      expect(result.type).toBe('object');
+      expect(result.hasOnclick).toBe(true);
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+
+  test('multiple notifications can be created sequentially', async () => {
+    let electronApp, userDataDir;
+    try {
+      ({ electronApp, userDataDir } = await launchApp('electron'));
+      const mainWindow = await getMainWindow(electronApp);
+      expect(mainWindow).toBeTruthy();
+
+      await mainWindow.waitForLoadState('load', { timeout: 30000 });
+
+      // This is the core regression test: Teams creates multiple notifications
+      // in sequence. If the stub is missing lifecycle methods, Teams' state
+      // machine breaks and stops calling new Notification() after the first.
+      const result = await mainWindow.evaluate(() => {
+        const stubs = [];
+        for (let i = 0; i < 5; i++) {
+          const n = new window.Notification(`Test ${i}`, { body: `body ${i}` });
+          stubs.push({
+            hasAddEventListener: typeof n.addEventListener === 'function',
+            hasClose: typeof n.close === 'function',
+          });
+        }
+        return stubs;
+      });
+
+      expect(result).toHaveLength(5);
+      for (const stub of result) {
+        expect(stub.hasAddEventListener).toBe(true);
+        expect(stub.hasClose).toBe(true);
+      }
+    } finally {
+      await cleanup(electronApp, userDataDir);
+    }
+  });
+});