Do not crash on/avoid index out of bounds

app/src/main/java/com/keylesspalace/tusky/components/notifications/NotificationsFragment.kt

@@ -161,7 +161,7 @@ class NotificationsFragment :
                 binding.recyclerView,
                 this
             ) { pos: Int ->
-                val notification = adapter.snapshot()[pos]
+                val notification = adapter.snapshot().getOrNull(pos)
                 // We support replies only for now
                 if (notification is NotificationViewData) {
                     notification.statusViewData

app/src/main/java/com/keylesspalace/tusky/components/timeline/TimelineFragment.kt

@@ -478,7 +478,7 @@ class TimelineFragment :
     override fun onLoadMore(position: Int) {
         val placeholder = adapter.peek(position)?.asPlaceholderOrNull() ?: return
         loadMorePosition = position
-        statusIdBelowLoadMore = adapter.peek(position + 1)?.id
+        statusIdBelowLoadMore = if (position + 1 < adapter.itemCount) adapter.peek(position + 1)?.id else null
         viewModel.loadMore(placeholder.id)
     }