FiX

Signed-off-by: TRAfoer <lhf190@outlook.com>

Assets/Scripts/DynamicUI/Timeline/Timeline.cs

@@ -140,6 +140,7 @@ namespace Ichni.Editor
         public RectTransform moveTabPoint;
         public void Elementfind(GameElement element)
         {
+            if (element == null) return;
             foreach (var i in element.childElementList)
             {
                 if (i is NoteBase)