diff --git a/vector/src/main/java/im/vector/app/features/notifications/NotifiableEventProcessor.kt b/vector/src/main/java/im/vector/app/features/notifications/NotifiableEventProcessor.kt
index bf9e805fc8..782f70645b 100644
--- a/vector/src/main/java/im/vector/app/features/notifications/NotifiableEventProcessor.kt
+++ b/vector/src/main/java/im/vector/app/features/notifications/NotifiableEventProcessor.kt
@@ -17,6 +17,8 @@
 package im.vector.app.features.notifications
 
 import im.vector.app.features.invite.AutoAcceptInvites
+import im.vector.app.features.notifications.Processed.KEEP
+import im.vector.app.features.notifications.Processed.REMOVE
 import javax.inject.Inject
 
 class NotifiableEventProcessor @Inject constructor(
@@ -24,20 +26,26 @@ class NotifiableEventProcessor @Inject constructor(
         private val autoAcceptInvites: AutoAcceptInvites
 ) {
 
-    fun process(eventList: List<NotifiableEvent>, currentRoomId: String?): Map<String, NotifiableEvent?> {
-        return eventList.associateBy { it.eventId }
-                .mapValues { (_, value) ->
-                    when (value) {
-                        is InviteNotifiableEvent  -> if (autoAcceptInvites.hideInvites) null else value
-                        is NotifiableMessageEvent -> if (shouldIgnoreMessageEventInRoom(currentRoomId, value.roomId) || outdatedDetector.isMessageOutdated(value)) {
-                            null
-                        } else value
-                        is SimpleNotifiableEvent  -> value
-                    }
-                }
+    fun process(eventList: List<NotifiableEvent>, currentRoomId: String?): List<Pair<Processed, NotifiableEvent>> {
+        return eventList.map {
+            when (it) {
+                is InviteNotifiableEvent  -> if (autoAcceptInvites.hideInvites) REMOVE else KEEP
+                is NotifiableMessageEvent -> if (shouldIgnoreMessageEventInRoom(currentRoomId, it.roomId) || outdatedDetector.isMessageOutdated(it)) {
+                    REMOVE
+                } else KEEP
+                is SimpleNotifiableEvent  -> KEEP
+            } to it
+        }
     }
 
     private fun shouldIgnoreMessageEventInRoom(currentRoomId: String?, roomId: String?): Boolean {
         return currentRoomId != null && roomId == currentRoomId
     }
 }
+
+enum class Processed {
+    KEEP,
+    REMOVE
+}
+
+fun List<Pair<Processed, NotifiableEvent>>.onlyKeptEvents() = filter { it.first == KEEP }.map { it.second }
diff --git a/vector/src/main/java/im/vector/app/features/notifications/NotificationDrawerManager.kt b/vector/src/main/java/im/vector/app/features/notifications/NotificationDrawerManager.kt
index 43d9eff185..c73b4b2a9c 100644
--- a/vector/src/main/java/im/vector/app/features/notifications/NotificationDrawerManager.kt
+++ b/vector/src/main/java/im/vector/app/features/notifications/NotificationDrawerManager.kt
@@ -56,7 +56,7 @@ class NotificationDrawerManager @Inject constructor(private val context: Context
     }
 
     private val eventList = loadEventInfo()
-    private var renderedEventsList = emptyMap<String, NotifiableEvent?>()
+    private var renderedEventsList = emptyList<Pair<Processed, NotifiableEvent>>()
     private val avatarSize = context.resources.getDimensionPixelSize(R.dimen.profile_avatar_size)
     private var currentRoomId: String? = null
 
@@ -236,10 +236,12 @@ class NotificationDrawerManager @Inject constructor(private val context: Context
         val eventsToRender = synchronized(eventList) {
             notifiableEventProcessor.process(eventList, currentRoomId).also {
                 eventList.clear()
-                eventList.addAll(it.values.filterNotNull())
+                eventList.addAll(it.onlyKeptEvents())
             }
         }
 
+
+
         if (renderedEventsList == eventsToRender) {
             Timber.d("Skipping notification update due to event list not changing")
         } else {
diff --git a/vector/src/main/java/im/vector/app/features/notifications/NotificationFactory.kt b/vector/src/main/java/im/vector/app/features/notifications/NotificationFactory.kt
index d5de0221f6..88f21a02a6 100644
--- a/vector/src/main/java/im/vector/app/features/notifications/NotificationFactory.kt
+++ b/vector/src/main/java/im/vector/app/features/notifications/NotificationFactory.kt
@@ -40,14 +40,14 @@ class NotificationFactory @Inject constructor(
 
     private fun NotifiableMessageEvent.canNotBeDisplayed() = isRedacted
 
-    fun Map<String, InviteNotifiableEvent?>.toNotifications(myUserId: String): List<OneShotNotification> {
-        return map { (roomId, event) ->
-            when (event) {
-                null -> OneShotNotification.Removed(key = roomId)
-                else -> OneShotNotification.Append(
+    fun List<Pair<Processed, InviteNotifiableEvent>>.toNotifications(myUserId: String): List<OneShotNotification> {
+        return map { (processed, event) ->
+            when (processed) {
+                Processed.REMOVE -> OneShotNotification.Removed(key = event.roomId)
+                Processed.KEEP   -> OneShotNotification.Append(
                         notificationUtils.buildRoomInvitationNotification(event, myUserId),
                         OneShotNotification.Append.Meta(
-                                key = roomId,
+                                key = event.roomId,
                                 summaryLine = event.description,
                                 isNoisy = event.noisy,
                                 timestamp = event.timestamp
@@ -58,14 +58,14 @@ class NotificationFactory @Inject constructor(
     }
 
     @JvmName("toNotificationsSimpleNotifiableEvent")
-    fun Map<String, SimpleNotifiableEvent?>.toNotifications(myUserId: String): List<OneShotNotification> {
-        return map { (eventId, event) ->
-            when (event) {
-                null -> OneShotNotification.Removed(key = eventId)
-                else -> OneShotNotification.Append(
+    fun List<Pair<Processed, SimpleNotifiableEvent>>.toNotifications(myUserId: String): List<OneShotNotification> {
+        return map { (processed, event) ->
+            when (processed) {
+                Processed.REMOVE -> OneShotNotification.Removed(key = event.eventId)
+                Processed.KEEP   -> OneShotNotification.Append(
                         notificationUtils.buildSimpleEventNotification(event, myUserId),
                         OneShotNotification.Append.Meta(
-                                key = eventId,
+                                key = event.eventId,
                                 summaryLine = event.description,
                                 isNoisy = event.noisy,
                                 timestamp = event.timestamp
diff --git a/vector/src/main/java/im/vector/app/features/notifications/NotificationRenderer.kt b/vector/src/main/java/im/vector/app/features/notifications/NotificationRenderer.kt
index 80391b1e06..31a99810e0 100644
--- a/vector/src/main/java/im/vector/app/features/notifications/NotificationRenderer.kt
+++ b/vector/src/main/java/im/vector/app/features/notifications/NotificationRenderer.kt
@@ -34,7 +34,7 @@ class NotificationRenderer @Inject constructor(private val notificationDisplayer
                myUserDisplayName: String,
                myUserAvatarUrl: String?,
                useCompleteNotificationFormat: Boolean,
-               eventsToProcess: Map<String, NotifiableEvent?>) {
+               eventsToProcess: List<Pair<Processed, NotifiableEvent>>) {
         val (roomEvents, simpleEvents, invitationEvents) = eventsToProcess.groupByType()
         with(notificationFactory) {
             val roomNotifications = roomEvents.toNotifications(myUserDisplayName, myUserAvatarUrl)
@@ -108,25 +108,28 @@ class NotificationRenderer @Inject constructor(private val notificationDisplayer
     }
 }
 
-private fun Map<String, NotifiableEvent?>.groupByType(): GroupedNotificationEvents {
+private fun List<Pair<Processed, NotifiableEvent>>.groupByType(): GroupedNotificationEvents {
     val roomIdToEventMap: MutableMap<String, MutableList<NotifiableMessageEvent>> = LinkedHashMap()
-    val simpleEvents: MutableMap<String, SimpleNotifiableEvent?> = LinkedHashMap()
-    val invitationEvents: MutableMap<String, InviteNotifiableEvent?> = LinkedHashMap()
-    forEach { (_, value) ->
-        when (value) {
-            is InviteNotifiableEvent  -> invitationEvents[value.roomId]
+    val simpleEvents: MutableList<Pair<Processed, SimpleNotifiableEvent>> = ArrayList()
+    val invitationEvents: MutableList<Pair<Processed, InviteNotifiableEvent>> = ArrayList()
+    forEach {
+        when (val event = it.second) {
+            is InviteNotifiableEvent  -> invitationEvents.add(it.asPair())
             is NotifiableMessageEvent -> {
-                val roomEvents = roomIdToEventMap.getOrPut(value.roomId) { ArrayList() }
-                roomEvents.add(value)
+                val roomEvents = roomIdToEventMap.getOrPut(event.roomId) { ArrayList() }
+                roomEvents.add(event)
             }
-            is SimpleNotifiableEvent  -> simpleEvents[value.eventId] = value
+            is SimpleNotifiableEvent  -> simpleEvents.add(it.asPair())
         }
     }
     return GroupedNotificationEvents(roomIdToEventMap, simpleEvents, invitationEvents)
 }
 
+@Suppress("UNCHECKED_CAST")
+private fun <T: NotifiableEvent> Pair<Processed, *>.asPair(): Pair<Processed, T> = this as Pair<Processed, T>
+
 data class GroupedNotificationEvents(
         val roomEvents: Map<String, List<NotifiableMessageEvent>>,
-        val simpleEvents: Map<String, SimpleNotifiableEvent?>,
-        val invitationEvents: Map<String, InviteNotifiableEvent?>
+        val simpleEvents: List<Pair<Processed, SimpleNotifiableEvent>>,
+        val invitationEvents: List<Pair<Processed, InviteNotifiableEvent>>
 )
diff --git a/vector/src/test/java/im/vector/app/features/notifications/NotifiableEventProcessorTest.kt b/vector/src/test/java/im/vector/app/features/notifications/NotifiableEventProcessorTest.kt
index 3e66f82bc3..154763afae 100644
--- a/vector/src/test/java/im/vector/app/features/notifications/NotifiableEventProcessorTest.kt
+++ b/vector/src/test/java/im/vector/app/features/notifications/NotifiableEventProcessorTest.kt
@@ -37,7 +37,7 @@ class NotifiableEventProcessorTest {
                 aSimpleNotifiableEvent(eventId = "event-2")
         )
 
-        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM)
+        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM, renderedEventsList = renderedEventsList)
 
         result shouldBeEqualTo aProcessedNotificationEvents(
                 simpleEvents = mapOf(
@@ -56,7 +56,7 @@ class NotifiableEventProcessorTest {
                 anInviteNotifiableEvent(roomId = "room-2")
         )
 
-        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM)
+        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM, renderedEventsList = renderedEventsList)
 
         result shouldBeEqualTo aProcessedNotificationEvents(
                 invitationEvents = mapOf(
@@ -75,7 +75,7 @@ class NotifiableEventProcessorTest {
                 anInviteNotifiableEvent(roomId = "room-2")
         )
 
-        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM)
+        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM, renderedEventsList = renderedEventsList)
 
         result shouldBeEqualTo aProcessedNotificationEvents(
                 invitationEvents = mapOf(
@@ -91,7 +91,7 @@ class NotifiableEventProcessorTest {
         val (events) = createEventsList(aNotifiableMessageEvent(eventId = "event-1", roomId = "room-1"))
         outdatedDetector.givenEventIsOutOfDate(events[0])
 
-        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM)
+        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM, renderedEventsList = renderedEventsList)
 
         result shouldBeEqualTo aProcessedNotificationEvents(
                 roomEvents = mapOf(
@@ -106,7 +106,7 @@ class NotifiableEventProcessorTest {
         val (events, originalEvents) = createEventsList(aNotifiableMessageEvent(eventId = "event-1", roomId = "room-1"))
         outdatedDetector.givenEventIsInDate(events[0])
 
-        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM)
+        val result = eventProcessor.process(events, currentRoomId = NOT_VIEWING_A_ROOM, renderedEventsList = renderedEventsList)
 
         result shouldBeEqualTo aProcessedNotificationEvents(
                 roomEvents = mapOf(
@@ -120,7 +120,7 @@ class NotifiableEventProcessorTest {
     fun `given viewing the same room as message event when processing then removes message`() {
         val (events) = createEventsList(aNotifiableMessageEvent(eventId = "event-1", roomId = "room-1"))
 
-        val result = eventProcessor.process(events, currentRoomId = "room-1")
+        val result = eventProcessor.process(events, currentRoomId = "room-1", renderedEventsList = renderedEventsList)
 
         result shouldBeEqualTo aProcessedNotificationEvents(
                 roomEvents = mapOf(