diff --git a/hive-c0re/assets/app.js b/hive-c0re/assets/app.js
index 2409710..2da6459 100644
--- a/hive-c0re/assets/app.js
+++ b/hive-c0re/assets/app.js
@@ -82,15 +82,30 @@
       unmute.addEventListener('click', () => { setMuted(false); renderControls(); });
       renderControls();
     }
-    function show(title, body) {
-      if (!supported || Notification.permission !== 'granted' || isMuted()) return;
+    function show(title, body, tag) {
+      if (!supported) {
+        console.debug('notify: Notification API not supported');
+        return;
+      }
+      if (Notification.permission !== 'granted') {
+        console.debug('notify: permission not granted', Notification.permission);
+        return;
+      }
+      if (isMuted()) {
+        console.debug('notify: muted');
+        return;
+      }
       try {
+        // Per-event tag so distinct messages stack instead of
+        // collapsing into one slot. Caller passes a unique tag per
+        // notification kind/id; we don't fall back to 'hyperhive'
+        // because that one tag would replace itself on every fire.
         const n = new Notification(title, {
           body,
-          tag: 'hyperhive',  // collapse rapid bursts
-          icon: '/static/dashboard.css',  // any same-origin asset works as a favicon stand-in
+          tag: tag || ('hyperhive:' + Date.now()),
         });
         n.onclick = () => { window.focus(); n.close(); };
+        console.debug('notify: shown', title, 'tag=', tag);
       } catch (err) {
         console.warn('notification show failed', err);
       }
@@ -124,12 +139,14 @@
       if (seenApprovals.has(a.id)) continue;
       seenApprovals.add(a.id);
       const verb = a.kind === 'spawn' ? 'spawn approval' : 'config commit';
-      NOTIF.show('◆ approval #' + a.id, `${verb} for ${a.agent}`);
+      NOTIF.show('◆ approval #' + a.id, `${verb} for ${a.agent}`,
+        'hyperhive:approval:' + a.id);
     }
     for (const q of questions) {
       if (seenQuestions.has(q.id)) continue;
       seenQuestions.add(q.id);
-      NOTIF.show('◆ manager asks', q.question.slice(0, 120));
+      NOTIF.show('◆ manager asks', q.question.slice(0, 120),
+        'hyperhive:question:' + q.id);
     }
     // operator_inbox: only notify on truly new ids — sse already
     // handles single-message notifications, but if the operator
@@ -658,7 +675,13 @@
       // the OS notification center.
       if (m.kind === 'sent' && m.to === 'operator') {
         refreshState();
-        NOTIF.show('◆ ' + m.from + ' → operator', String(m.body || '').slice(0, 200));
+        NOTIF.show(
+          '◆ ' + m.from + ' → operator',
+          String(m.body || '').slice(0, 200),
+          // Unique-per-arrival tag so a burst stacks instead of
+          // overwriting itself in the OS notification center.
+          'hyperhive:msg:' + m.at + ':' + Math.random().toString(36).slice(2, 6),
+        );
       }
       const row = document.createElement('div');
       row.className = 'msgrow ' + m.kind;