Moving the Scrollbar via clicking no longer works after the first-click when page size is too small

Steps to reproduce:
1. Open the attached “ScrollbarBug 2.zip” project
2. Open the “SampleScene”
3. Enter Play Mode
4. Click the middle of the Scrollbar to scroll the text by pages
5. Click the middle of the Scrollbar to scroll again

Expected result: Scrollbar scrolls down the list
Actual result: Scrollbar becomes unresponsive to clicks

Reproducible in: 2022.3.51f1, 6000.0.25f1, 6000.1.0a3
Couldn’t test in: 2021.3.45f1 (because UI Toolkit’s TreeView component didn’t exist)

Reproducible on: Windows 11, macOS (Silicon)
Not reproducible on: No other environment tested