This will set the clip label to "flip" which is better than showing full class name.
[CustomTimelineEditor(typeof(SpineSkeletonFlipClip))]
public class SpineSkeletonFlipClipEditor : ClipEditor
{
public override void OnClipChanged(TimelineClip clip)
{
var flipClip = (SpineSkeletonFlipClip)clip.asset;
if (flipClip != null)
{
// TODO: you can custom the label based on setting here.
clip.displayName = "Flip";
}
}
}