App UI Tabs throws "Cannot scroll to a VisualElement that's not a child of the ScrollView content-container" when all TabItems are deleted in UI Builder

How to reproduce:

1. Open the attached "IN-149611" project
2. Open Assets > Scenes > “NewUXMLTemplate.uxml” in UI Builder
3. In the top middle-part or UI Builder locate “Viewport” > “Built-in Default Runtime Theme”
4. Change theme to any “App UI” theme
5. In UI Builder Hierarchy expand “NewUXMLTemplate.uxml” > “Tabs” > “appui-tabs_scroll-view” > “unity-content-and-vertical-scroll-container” > “unity-content-viewport” > “unity-content-container” > “appui-tabs_container”
6. Select all “TabItem” elements in UI Builder Hierarchy
7. Delete them
8. Observe the Console

Actual result: "ArgumentException: Cannot scroll to a VisualElement that's not a child of the ScrollView content-container" is logged
Expected result: The TabItems are removed and no exception is logged

Reproducible with: 2.0.0-pre.16 (6000.0.0f1); 2.2.2, 3.0.0-pre.1 (6000.6.0f1, 6000.7.0a6)
Not reproducible with: 2.0.0-pre.15 (6000.0.0f1)

Reproducible on: Windows 11 (25H2), Windows 10 (by user)
Not reproducible on: No other environments tested