Hey! I'm trying to make custom child/parent tracks for the timeline which behave similar to the Animation Track, i.e. a parent root track with the binding and then child tracks for different layers of animation. I'm using the CreateTrack<T> function on the parent TimelineAsset to create a new track on a specified parent but it throws an exception: InvalidOperationException: Cannot assign a child of type T to a parent of type T Where T is the type of my track asset. Is there an attribute or something I need to do to allow custom tracks to be able to be children of other tracks?? Also Ideally I'd be able to add a custom context menu item to allow creating child tracks in the same way the 'Add Override Track' menu works for Animator Tracks (see below). How is this done? The usual way of adding a [MenuItem] / [ContextMenu] attribute doesn't seem to work for timelines? Thanks!