Steps to reproduce:

1. Create a new Unity project using the Universal 3D template
2. Create a new Terrain (GameObject > 3D Object > Terrain)
3. Click the "Paint Terrain" button in the Inspector window
4. Change the Brush Size in the Scene View tool
5. Observe the Brush Size in the Inspector window

Actual results: Brush Size does not get updated in the Inspector window

Expected results: Brush Size in the Scene View and Inspector window is the same

Reproducible with versions: 6000.0.50f1, 6000.1.6f1, 6000.2.0b4

Tested on (OS): macOS SIlicon Sequoia 15.3

Notes:

• The Brush Size in the Inspector window updates when mouse is hovered on it
• If the Brush Size is changed in the Inspector window, the Scene View tool Brush Size updates with no issues.
• The same issue impacts the Opacity slider as well