To reproduce:
1) Create new project
2) Create script which would have a public array, like this: (C# example)

using UnityEngine;
public class Foo : MonoBehaviour {
public int[] i = new int[5];
}

3) Attach it to camera
4) Change the array values so each element would be different
5) Highlight one of the element values(i.e. click on one of the numbers) and right click the element to delete it from array. It looks like it deletes an element below it. Click on some other element and now array correctly reflects that the element highlighted was deleted and not the element below. To visualize, if in array of [1,2,3,4,5], if you highlight value '2' and delete it, it will at first show [1,2,4,5] but after selecting something else it will show [1,3,4,5]
6) If you just right click "Element X" part and delete it, the changes are shown immedieately. For example, in same [1,2,3,4,5] array, if clicking on "Element 1" and clicking shift+del, it immeadiately shows [1,3,4,5]