Don't show NEW timeline divider when not applicable in previews

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelineStateProvider.kt

@@ -23,7 +23,6 @@ import io.element.android.features.messages.impl.timeline.model.anAggregatedReac
 import io.element.android.features.messages.impl.timeline.model.event.TimelineItemEventContent
 import io.element.android.features.messages.impl.timeline.model.event.aTimelineItemStateEventContent
 import io.element.android.features.messages.impl.timeline.model.event.aTimelineItemTextContent
-import io.element.android.features.messages.impl.timeline.model.virtual.TimelineItemReadMarkerModel
 import io.element.android.features.messages.impl.timeline.model.virtual.aTimelineItemDaySeparatorModel
 import io.element.android.features.messages.impl.typing.TypingNotificationState
 import io.element.android.features.messages.impl.typing.aTypingNotificationState
@@ -90,13 +89,6 @@ fun aTimelineState(
     )
 }
 
-internal fun aTimelineItemReadMarker(): TimelineItem.Virtual {
-    return TimelineItem.Virtual(
-        id = UniqueId(UUID.randomUUID().toString()),
-        model = TimelineItemReadMarkerModel,
-    )
-}
-
 internal fun aTimelineItemList(content: TimelineItemEventContent): ImmutableList<TimelineItem> {
     return persistentListOf(
         // 3 items (First Middle Last) with isMine = false

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelineView.kt

@@ -546,12 +546,11 @@ private fun TimelineViewWithReadMarker(
     unreadMessagesCount: Int,
     newMessagesCount: Int,
 ) {
-    val readMarker = aTimelineItemReadMarker()
     val timelineItems = persistentListOf<TimelineItem>(
         aTimelineItemEvent(isMine = false),
         aTimelineItemEvent(isMine = false),
         aTimelineItemEvent(isMine = true),
-        readMarker,
+        aTimelineItemEvent(isMine = false),
         aTimelineItemEvent(isMine = false),
         aTimelineItemEvent(isMine = false),
     )
@@ -561,7 +560,10 @@ private fun TimelineViewWithReadMarker(
         TimelineView(
             state = aTimelineState(
                 timelineItems = timelineItems,
-                readMarkerIndex = timelineItems.indexOf(readMarker),
+                // Index points past the loaded items, mirroring the real-world state the FAB
+                // represents: the user has scrolled past the read marker, so it's no longer in
+                // view. The actual scroll target doesn't matter for a static preview.
+                readMarkerIndex = timelineItems.size,
                 unreadMessagesCount = unreadMessagesCount,
                 newMessagesCount = newMessagesCount,
             ),
@@ -590,7 +592,7 @@ internal fun TimelineViewWithReadMarkerNoBadgesPreview() = ElementPreview {
 @PreviewsDayNight
 @Composable
 internal fun TimelineViewWithReadMarkerPreview() = ElementPreview {
-    TimelineViewWithReadMarker(unreadMessagesCount = 3, newMessagesCount = 12)
+    TimelineViewWithReadMarker(unreadMessagesCount = 3, newMessagesCount = 0)
 }
 
 @PreviewsDayNight