Sometimes, when using other formats than 1:1, for example 9:16 for an animation, either the hair or lower body is cut/excluded from the animation part. So while the animation moves, the cut/excluded part is static. It doesn't look good with two-thirds of a head or only the upper body moving, while the rest is static and out of alignment. So it would be nice to be able to define what area should be animated. Or even better yet, that no areas of the puppet, upper or lower, is cut/excluded from the animation.