diff --git a/backend/src/routes/push.js b/backend/src/routes/push.js
index 61521ff..9139786 100644
--- a/backend/src/routes/push.js
+++ b/backend/src/routes/push.js
@@ -112,7 +112,10 @@ router.post('/unsubscribe', authMiddleware, async (req, res) => {
   } catch (e) { res.status(500).json({ error: e.message }); }
 });
 
-// Send a test push to the requesting user's own device — for diagnosing FCM setup
+// Send a test push to the requesting user's own device — for diagnosing FCM setup.
+// mode=data (default): data-only message handled by the service worker onBackgroundMessage.
+// mode=browser: webpush.notification message handled by Chrome directly (bypasses SW).
+//   Use mode=browser to check if FCM delivery itself works when the SW is not involved.
 router.post('/test', authMiddleware, async (req, res) => {
   try {
     const subs = await query(req.schema,
@@ -130,25 +133,42 @@ router.post('/test', authMiddleware, async (req, res) => {
       return res.status(503).json({ error: 'Firebase Admin not initialised on server — check FIREBASE_SERVICE_ACCOUNT in .env' });
     }
 
+    const mode = req.query.mode === 'browser' ? 'browser' : 'data';
+
     const results = [];
     for (const sub of subs) {
       try {
-        await messaging.send({
+        const message = {
           token: sub.fcm_token,
-          data: {
-            title:   'RosterChirp Test',
-            body:    'Push notifications are working! 🎉',
-            url:     '/',
-            groupId: '',
-          },
           android: { priority: 'high' },
           webpush: { headers: { Urgency: 'high' } },
-        });
-        results.push({ device: sub.device, status: 'sent' });
-        console.log(`[Push] Test notification sent to user ${req.user.id} device=${sub.device}`);
+        };
+
+        if (mode === 'browser') {
+          // Chrome displays the notification directly — onBackgroundMessage does NOT fire.
+          // Use this to verify FCM delivery works independently of the service worker.
+          message.webpush.notification = {
+            title: 'RosterChirp Test (browser)',
+            body:  'FCM delivery confirmed — Chrome handled this directly.',
+            icon:  '/icons/icon-192.png',
+          };
+          message.webpush.fcm_options = { link: '/' };
+        } else {
+          // data-only — service worker onBackgroundMessage must show the notification.
+          message.data = {
+            title:   'RosterChirp Test',
+            body:    'Push notifications are working!',
+            url:     '/',
+            groupId: '',
+          };
+        }
+
+        await messaging.send(message);
+        results.push({ device: sub.device, mode, status: 'sent' });
+        console.log(`[Push] Test (${mode}) sent to user ${req.user.id} device=${sub.device}`);
       } catch (err) {
-        results.push({ device: sub.device, status: 'failed', error: err.message, code: err.code });
-        console.error(`[Push] Test notification failed for user ${req.user.id} device=${sub.device}:`, err.message);
+        results.push({ device: sub.device, mode, status: 'failed', error: err.message, code: err.code });
+        console.error(`[Push] Test (${mode}) failed for user ${req.user.id} device=${sub.device}:`, err.message);
       }
     }
     res.json({ results });
diff --git a/frontend/public/sw.js b/frontend/public/sw.js
index e0ba63a..1300512 100644
--- a/frontend/public/sw.js
+++ b/frontend/public/sw.js
@@ -54,6 +54,7 @@ self.addEventListener('fetch', (event) => {
 let badgeCount = 0;
 
 function showRosterChirpNotification(data) {
+  console.log('[SW] showRosterChirpNotification:', JSON.stringify(data));
   badgeCount++;
   if (self.navigator?.setAppBadge) self.navigator.setAppBadge(badgeCount).catch(() => {});
 
@@ -64,17 +65,29 @@ function showRosterChirpNotification(data) {
     data:    { url: data.url || '/' },
     tag:     data.groupId ? `rosterchirp-group-${data.groupId}` : 'rosterchirp-message',
     renotify: true,
-    vibrate:  [200, 100, 200],  // haptic pattern — also activates the OS sound channel
+    vibrate:  [200, 100, 200],
   });
 }
 
 // ── FCM background messages ───────────────────────────────────────────────────
 if (messaging) {
   messaging.onBackgroundMessage((payload) => {
+    console.log('[SW] onBackgroundMessage received, data:', JSON.stringify(payload.data));
     return showRosterChirpNotification(payload.data || {});
   });
+} else {
+  console.warn('[SW] Firebase messaging not initialised — push notifications disabled');
 }
 
+// ── Raw push event (fallback diagnostic) ─────────────────────────────────────
+// Fires for every push event BEFORE the Firebase SDK handles it.
+// Log it so chrome://inspect shows whether the SW is even waking up.
+self.addEventListener('push', (event) => {
+  console.log('[SW] push event received, hasData:', !!event.data, 'text:', event.data?.text?.()?.slice(0, 120));
+  // Note: Firebase compat SDK registers its own push listener and handles display.
+  // This listener is diagnostic only — do not call showNotification() here.
+});
+
 // ── Notification click ────────────────────────────────────────────────────────
 self.addEventListener('notificationclick', (event) => {
   event.notification.close();
diff --git a/frontend/src/components/ProfileModal.jsx b/frontend/src/components/ProfileModal.jsx
index a3618f4..cf76e7e 100644
--- a/frontend/src/components/ProfileModal.jsx
+++ b/frontend/src/components/ProfileModal.jsx
@@ -180,24 +180,50 @@ export default function ProfileModal({ onClose }) {
                 • App is backgrounded when the test fires
               </p>
             </div>
-            <button
-              className="btn btn-primary"
-              disabled={pushTesting}
-              onClick={async () => {
-                setPushTesting(true);
-                setPushResult(null);
-                try {
-                  const { results } = await api.testPush();
-                  setPushResult({ ok: true, results });
-                } catch (e) {
-                  setPushResult({ ok: false, error: e.message });
-                } finally {
-                  setPushTesting(false);
-                }
-              }}
-            >
-              {pushTesting ? 'Sending…' : 'Send Test Notification'}
-            </button>
+            <div className="flex gap-2">
+              <button
+                className="btn btn-primary"
+                style={{ flex: 1 }}
+                disabled={pushTesting}
+                onClick={async () => {
+                  setPushTesting(true);
+                  setPushResult(null);
+                  try {
+                    const { results } = await api.testPush('data');
+                    setPushResult({ ok: true, results, mode: 'data' });
+                  } catch (e) {
+                    setPushResult({ ok: false, error: e.message });
+                  } finally {
+                    setPushTesting(false);
+                  }
+                }}
+              >
+                {pushTesting ? 'Sending…' : 'Test (via SW)'}
+              </button>
+              <button
+                className="btn btn-secondary"
+                style={{ flex: 1 }}
+                disabled={pushTesting}
+                onClick={async () => {
+                  setPushTesting(true);
+                  setPushResult(null);
+                  try {
+                    const { results } = await api.testPush('browser');
+                    setPushResult({ ok: true, results, mode: 'browser' });
+                  } catch (e) {
+                    setPushResult({ ok: false, error: e.message });
+                  } finally {
+                    setPushTesting(false);
+                  }
+                }}
+              >
+                {pushTesting ? 'Sending…' : 'Test (via Browser)'}
+              </button>
+            </div>
+            <div style={{ fontSize: 12, color: 'var(--text-tertiary)', lineHeight: 1.4 }}>
+              <strong>Test (via SW)</strong> — normal production path, service worker shows notification.<br/>
+              <strong>Test (via Browser)</strong> — bypasses service worker; Chrome displays directly.
+            </div>
             {pushResult && (
               <div style={{
                 padding: '10px 12px',
diff --git a/frontend/src/utils/api.js b/frontend/src/utils/api.js
index c7b437d..5329f63 100644
--- a/frontend/src/utils/api.js
+++ b/frontend/src/utils/api.js
@@ -170,7 +170,7 @@ export const api = {
   getFirebaseConfig: () => req('GET', '/push/firebase-config'),
   subscribePush: (fcmToken) => req('POST', '/push/subscribe', { fcmToken }),
   unsubscribePush: () => req('POST', '/push/unsubscribe'),
-  testPush: () => req('POST', '/push/test'),
+  testPush: (mode = 'data') => req('POST', `/push/test?mode=${mode}`),
 
   // Link preview
   getLinkPreview: (url) => req('GET', `/link-preview?url=${encodeURIComponent(url)}`),