How to reproduce:
1. Create a new Unity project
2. Create a new UI Document and open it
3. Open the three-dot menu of the UI Builder window and open the UI Toolkit Debugger
4. Click and drag the tab separator to resize the Layout and Styles tabs
5. Move the mouse quickly while hovering on the "EditorPanelRootElement"
6. Observe the results
Expected results: No highlighting of the UI element occurs
Actual results: When moving the mouse fast a brief highlighting of the UI Element occurs resulting in the flickering
Reproducible with: 2021.3.40f1, 2022.3.39f1, 6000.0.13f1
Reproducible on: macOS Sonoma 14.5 (M1)
Notes: In 6000.0.13f1 the mouse cursor is not changed to the arrows when resizing but hovered on the UI Element. However, in 2021.3.40f1, it can be observed that during the fast resizing, the mouse quickly changes from the arrow to a standard cursor, resulting in selecting the UI Element and highlighting.