How to reproduce:
1. Open the attached “IN-147147“ project
2. Open Scenes>”SampleScene”
3. Open UI> “UxmlTest.uxml” in UI Builder
4. In UI Builder Hierarchy, locate the “MyUxmlB”
5. In UI Builder Inspector, locate “Test Test" attribute
6. Press right mouse button on “Test Test” attribute > add a binding > paste “stringForTesting” in “Data Source Path”
7. Enter Play mode
8. Observe the Console
Actual: UI Builder writes the binding as property="TestTest" (the parent's property), so both elements call MyUxmlA's setter ("set in A" twice); MyUxmlB's own property is never bound and no binding icon shows on B
Expected: the binding targets MyUxmlB's own property > "set in B", with the binding icon shown
Reproducible with: 6000.0.0f1, 6000.0.80f1, 6000.3.20f1, 6000.5.5f1, 6000.6.0b5, 6000.7.0a3
Reproducible on: Windows 11(25H2)
Not reproducible on: No other environments tested
Note: MyUxmlB's ToastToast [UxmlAttribute("test-test")] collides with the inherited TestTest (also test-test). UI Builder resolves the shared name to the base property