"NullReferenceException" thrown when modifying a UI Document while a Scene containing a GameObject with any UI Document and a missing script component is open

How to reproduce:
1. Open the attached project "IN-124664"
2. Open "SampleScene"
3. In the Project window open the "Assets/UIDoc" UI Document
4. In the UI Builder Hierarchy, select "VisualElement"
5. In the UI Builder Inspector, change Tabindex value

Actual result: "NullReferenceException: Object reference not set to an instance of an object" error is thrown in the Console
Expected result: No error is thrown in the Console

Reproducible with: 2022.1.0a1, 6000.0.63f1, 6000.2.15f1, 6000.3.0f1, 6000.4.0a5, 6000.5.0a2

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Workaround: Removing the missing script component

Note: error is thrown when modifying any value or adding elements into Hierarchy