diff --git a/app/src/main/java/im/vector/riotredesign/core/extensions/Event.kt b/app/src/main/java/im/vector/riotredesign/core/extensions/Event.kt
index 098d1af5..d93877a6 100644
--- a/app/src/main/java/im/vector/riotredesign/core/extensions/Event.kt
+++ b/app/src/main/java/im/vector/riotredesign/core/extensions/Event.kt
@@ -17,12 +17,9 @@
 package im.vector.riotredesign.core.extensions
 
 import im.vector.matrix.android.api.session.events.model.Event
-import org.threeten.bp.Instant
+import im.vector.riotredesign.core.resources.DateProvider
 import org.threeten.bp.LocalDateTime
-import org.threeten.bp.ZoneId
-
 
 fun Event.localDateTime(): LocalDateTime {
-    val instant = Instant.ofEpochMilli(originServerTs ?: 0)
-    return LocalDateTime.ofInstant(instant, ZoneId.systemDefault())
+    return DateProvider.toLocalDateTime(originServerTs)
 }
\ No newline at end of file
diff --git a/app/src/main/java/im/vector/riotredesign/core/resources/DateProvider.kt b/app/src/main/java/im/vector/riotredesign/core/resources/DateProvider.kt
new file mode 100644
index 00000000..cc01bdf1
--- /dev/null
+++ b/app/src/main/java/im/vector/riotredesign/core/resources/DateProvider.kt
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.riotredesign.core.resources
+
+import org.threeten.bp.Instant
+import org.threeten.bp.LocalDateTime
+import org.threeten.bp.ZoneId
+
+object DateProvider {
+
+    private val zoneId = ZoneId.systemDefault()
+
+    fun toLocalDateTime(timestamp: Long?): LocalDateTime {
+        val instant = Instant.ofEpochMilli(timestamp ?: 0)
+        return LocalDateTime.ofInstant(instant, zoneId)
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/im/vector/riotredesign/features/home/HomeNavigator.kt b/app/src/main/java/im/vector/riotredesign/features/home/HomeNavigator.kt
index 7ffe463b..4fb84ea1 100644
--- a/app/src/main/java/im/vector/riotredesign/features/home/HomeNavigator.kt
+++ b/app/src/main/java/im/vector/riotredesign/features/home/HomeNavigator.kt
@@ -30,13 +30,13 @@ class HomeNavigator {
 
     var activity: HomeActivity? = null
 
-    private var currentRoomId: String? = null
+    private var rootRoomId: String? = null
 
     fun openRoomDetail(roomId: String,
                        eventId: String?,
                        addToBackstack: Boolean = false) {
         Timber.v("Open room detail $roomId - $eventId - $addToBackstack")
-        if (!addToBackstack && isRoomOpened(roomId)) {
+        if (!addToBackstack && isRoot(roomId)) {
             return
         }
         activity?.let {
@@ -46,7 +46,7 @@ class HomeNavigator {
             if (addToBackstack) {
                 it.addFragmentToBackstack(roomDetailFragment, R.id.homeDetailFragmentContainer, roomId)
             } else {
-                currentRoomId = roomId
+                rootRoomId = roomId
                 clearBackStack(it.supportFragmentManager)
                 it.replaceFragment(roomDetailFragment, R.id.homeDetailFragmentContainer)
             }
@@ -61,9 +61,7 @@ class HomeNavigator {
         Timber.v("Open user detail $userId")
     }
 
-    fun isRoomOpened(roomId: String): Boolean {
-        return currentRoomId == roomId
-    }
+    // Private Methods *****************************************************************************
 
     private fun clearBackStack(fragmentManager: FragmentManager) {
         if (fragmentManager.backStackEntryCount > 0) {
@@ -72,4 +70,8 @@ class HomeNavigator {
         }
     }
 
+    private fun isRoot(roomId: String): Boolean {
+        return rootRoomId == roomId
+    }
+
 }
\ No newline at end of file
diff --git a/app/src/main/java/im/vector/riotredesign/features/home/room/detail/timeline/TimelineEventController.kt b/app/src/main/java/im/vector/riotredesign/features/home/room/detail/timeline/TimelineEventController.kt
index 0d12ae8e..e610931c 100644
--- a/app/src/main/java/im/vector/riotredesign/features/home/room/detail/timeline/TimelineEventController.kt
+++ b/app/src/main/java/im/vector/riotredesign/features/home/room/detail/timeline/TimelineEventController.kt
@@ -37,9 +37,6 @@ class TimelineEventController(private val roomId: String,
         EpoxyAsyncUtil.getAsyncBackgroundHandler(),
         EpoxyAsyncUtil.getAsyncBackgroundHandler()
 ) {
-    init {
-        setFilterDuplicates(true)
-    }
 
     private var isLoadingForward: Boolean = false
     private var isLoadingBackward: Boolean = false
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/session/room/members/RoomMemberExtractor.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/session/room/members/RoomMemberExtractor.kt
index 5ab87285..79d4a176 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/session/room/members/RoomMemberExtractor.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/session/room/members/RoomMemberExtractor.kt
@@ -34,22 +34,23 @@ internal class RoomMemberExtractor(private val monarchy: Monarchy,
     private val cached = HashMap<String, RoomMember?>()
 
     fun extractFrom(event: EventEntity): RoomMember? {
-        if (cached.containsKey(event.eventId)) {
-            return cached[event.eventId]
-        }
         val sender = event.sender ?: return null
+        val cacheKey = sender + event.stateIndex
+        if (cached.containsKey(cacheKey)) {
+            return cached[cacheKey]
+        }
         // If the event is unlinked we want to fetch unlinked state events
         val unlinked = event.isUnlinked
         // When stateIndex is negative, we try to get the next stateEvent prevContent()
         // If prevContent is null we fallback to the Int.MIN state events content()
         val content = if (event.stateIndex <= 0) {
             baseQuery(monarchy, roomId, sender, unlinked).next(from = event.stateIndex)?.prevContent
-                    ?: baseQuery(monarchy, roomId, sender, unlinked).last(since = event.stateIndex)?.content
+            ?: baseQuery(monarchy, roomId, sender, unlinked).last(since = event.stateIndex)?.content
         } else {
             baseQuery(monarchy, roomId, sender, unlinked).last(since = event.stateIndex)?.content
         }
         val roomMember: RoomMember? = ContentMapper.map(content).toModel()
-        cached[event.eventId] = roomMember
+        cached[cacheKey] = roomMember
         return roomMember
     }