Color Picker feels less smooth when dragging a Variables Color property in UI Builder Inspector

Steps to reproduce:

1. Create a new 3D URP project
2. Create a new UI Document (Assets > Create > UI Toolkit > UI Document)
3. Open the .uxml file in UI Builder
4. Create a new USS file with a new selector (e.g. "test")
5. Select the newly created selector
6. In the Inspector, expand the "Variables" foldout
7. Click the "+" icon and add "Color" variable
8. Click on the Color Picker field
9. Click and drag inside the Color Picker to select different colors
10. Observe the Color Picker responsiveness

Actual results: The Color Picker feels slightly less smooth when dragging compared to other Color Pickers in the Editor

Expected results: The Color Picker should feel as smooth and responsive as other Color Pickers in the Editor

Reproducible with versions: 6000.3.13f1, 6000.4.3f1, 6000.5.0b4, 6000.6.0a3

Can’t test with versions: 6000.0.72f1 (Variables not available)

Tested on (OS): macOS 26.4, Ubuntu 24.04

Notes:

• The issue is subtle and not very noticeable, but the Color Picker does not feel as smooth as expected while dragging
• Does not reproduce with other Color Pickers in the Editor or the Color Picker in "Border" foldout in UI Builder