From 79309f5d54683d38992c0c9dfda98d2c238cdc6b Mon Sep 17 00:00:00 2001
From: StAkira <akira3weet@gmail.com>
Date: Wed, 14 Jun 2023 23:32:22 -0700
Subject: [PATCH] Fix nullness

---
 OpenUtau/Controls/TrackHeaderCanvas.cs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/OpenUtau/Controls/TrackHeaderCanvas.cs b/OpenUtau/Controls/TrackHeaderCanvas.cs
index 39951cd2e..fb9943be8 100644
--- a/OpenUtau/Controls/TrackHeaderCanvas.cs
+++ b/OpenUtau/Controls/TrackHeaderCanvas.cs
@@ -52,10 +52,13 @@ public TrackHeaderCanvas() {
             MessageBus.Current.Listen<TracksRefreshEvent>()
                 .Subscribe(_ => {
                     foreach (var (track, header) in trackHeaders) {
+                        if (header.ViewModel == null) {
+                            continue;
+                        }
                         if (PlaybackManager.Inst.SoloTrackExist && !track.Solo) {
                             header.ViewModel.Muted = true;
                         }
-                        header.ViewModel?.ManuallyRaise();
+                        header.ViewModel.ManuallyRaise();
                     }
                     if (trackAdder != null) {
                         trackAdder.TrackNo = trackHeaders.Count;