Fixes thread notifications instantly disappearing

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/summary/RoomSummaryUpdater.kt

@@ -114,14 +114,12 @@ internal class RoomSummaryUpdater @Inject constructor(
         roomSummaryEntity.notificationCount = unreadNotifications?.notificationCount ?: 0
 
         roomSummaryEntity.threadHighlightCount = unreadThreadNotifications
-                ?.map { it.value.highlightCount.takeIf { count -> (count ?: 0) > 0 } }
+                ?.count { (it.value.highlightCount ?: 0) > 0 }
-                ?.size
-                ?: 0
-        roomSummaryEntity.threadNotificationCount = unreadThreadNotifications
-                ?.map { it.value.notificationCount.takeIf { count -> (count ?: 0) > 0 } }
-                ?.size
                 ?: 0
 
+        roomSummaryEntity.threadNotificationCount = unreadThreadNotifications
+                ?.count { (it.value.notificationCount ?: 0) > 0 }
+                ?: 0
 
         if (membership != null) {
             roomSummaryEntity.membership = membership

vector/src/main/java/im/vector/app/features/home/room/detail/TimelineViewModel.kt

@@ -18,6 +18,7 @@ package im.vector.app.features.home.room.detail
 
 import android.net.Uri
 import androidx.annotation.IdRes
+import androidx.lifecycle.asFlow
 import com.airbnb.mvrx.Async
 import com.airbnb.mvrx.Fail
 import com.airbnb.mvrx.Loading
@@ -407,10 +408,27 @@ class TimelineViewModel @AssistedInject constructor(
      * Observe local unread threads.
      */
     private fun observeLocalThreadNotifications() {
-        if (room == null) return
+        val threadNotificationsSupported = session.homeServerCapabilitiesService().getHomeServerCapabilities().canUseThreadReadReceiptsAndNotifications
-        room.flow()
+        if (threadNotificationsSupported) {
-                .liveLocalUnreadThreadList()
+            room?.getRoomSummaryLive()
-                .execute {
+                    ?.asFlow()
+                    ?.onEach {
+                        it.getOrNull()?.let {
+                            setState {
+                                copy(
+                                        threadNotificationBadgeState = ThreadNotificationBadgeState(
+                                                numberOfLocalUnreadThreads = it.threadNotificationCount + it.threadHighlightCount,
+                                                isUserMentioned = it.threadHighlightCount > 0,
+                                        )
+                                )
+                            }
+                        }
+                    }
+                    ?.launchIn(viewModelScope)
+        } else {
+            room?.flow()
+                    ?.liveLocalUnreadThreadList()
+                    ?.execute {
                         val threadList = it.invoke()
                         val isUserMentioned = threadList?.firstOrNull { threadRootEvent ->
                             threadRootEvent.root.threadDetails?.threadNotificationState == ThreadNotificationState.NEW_HIGHLIGHTED_MESSAGE
@@ -424,6 +442,7 @@ class TimelineViewModel @AssistedInject constructor(
                         )
                     }
         }
+    }
 
     override fun handle(action: RoomDetailAction) {
         when (action) {