Inconsistency between adding script as component for gameobject and as behaviour in animation state (if user chooses None; it disappears)

2) How can we reproduce it using the example you attached
1 Create new project
2 Create new Animator Controller
3 Create an empty animation state and select it
4 Click on Add behaviour button
5 Enter some name and click Create
6 In Inspector for this animation - try to set "Script" and Choose None as behaviour
Actual result:
It disappears totally. In Add Component feature it just says you have no scripts assigned to this object.
Expected result:
It shouldn't disappear totally.