Steps to reproduce:
1. Download the attached project and open SampleScene
2. In the Hierarchy panel, or in the Scene view, select the Disc Light
3. In the Scene view, hold down the left mouse button on one of the gizmo handles (square dots on the spline) and begin dragging the mouse
4. Notice that when scaling, the gizmo "splits" in the process

Notes:
- Adjusting the disc light radius in the Inspector seems to work fine
- After scaling, deselecting and then selecting the disc light in the scene view fixes the issue with the gizmo