Mouse slide screen looping buggy on right hand side

Reproduction steps:
1. Open attached project "FunctionalityET.zip" and scene "SampleScene"
2. In Hierarchy view, select "Cube" GameObject
3. In Scene View, with Rotate / Scale / Rect / Transform tool, adjust property by sliding mouse to either left or right edge of the screen and beyond

Expected result: Looping is either allowed or not allowed consistently
Actual result: Looping is allowed and not allowed inconsistently. Right side looping causes erratic mouse movements on 2021.2.0a6

No looping: 2019.4.29f1, 2021.1.18f1, 2021.2.0b9, 2021.2.0a2
Looping on left side: 2020.3.17f1
Looping on both sides, but erratic on the right: 2021.2.0a3, 2021.2.0a6