Deduplicate desktop notifications

packages/electron/main.mjs

@@ -892,6 +892,37 @@ const focusForegroundWindow = () => {
 // click events to silently stop firing after ~1 min.
 // See https://blog.bloomca.me/2025/02/22/electron-mac-notifications
 const activeNotifications = new Set();
+const nativeNotificationClaims = new Map();
+const NATIVE_NOTIFICATION_DEDUPE_TTL_MS = 5000;
+
+const getNativeNotificationClaimKey = (payload) => {
+  const tag = typeof payload?.tag === 'string' ? payload.tag.trim() : '';
+  if (tag) return tag;
+  return [payload?.sessionId, payload?.kind, payload?.title, payload?.body]
+    .filter((value) => typeof value === 'string' && value.trim())
+    .map((value) => value.trim())
+    .join('|');
+};
+
+const claimNativeNotification = (payload) => {
+  const key = getNativeNotificationClaimKey(payload);
+  if (!key) return true;
+
+  const now = Date.now();
+  for (const [claimKey, claimedAt] of nativeNotificationClaims) {
+    if (now - claimedAt > NATIVE_NOTIFICATION_DEDUPE_TTL_MS) {
+      nativeNotificationClaims.delete(claimKey);
+    }
+  }
+
+  const claimedAt = nativeNotificationClaims.get(key) ?? 0;
+  if (now - claimedAt < NATIVE_NOTIFICATION_DEDUPE_TTL_MS) {
+    return false;
+  }
+
+  nativeNotificationClaims.set(key, now);
+  return true;
+};
 
 const maybeShowNativeNotification = (rawInput) => {
   const payload = normalizeNotificationInput(rawInput);
@@ -905,6 +936,10 @@ const maybeShowNativeNotification = (rawInput) => {
     return;
   }
 
+  if (!claimNativeNotification(payload)) {
+    return;
+  }
+
   const title = typeof payload.title === 'string' && payload.title.trim()
     ? payload.title.trim()
     : 'OpenChamber';