Steps to reproduce:
1. Create a new project
2. Create UI Document (Create > UI Toolkit > UI Document)
3. Double-click on the newly created UI Document to open UI Builder
4. Drag Visual Element to the Hierarchy
5. Open Filter dropdown section in Visual Element Inspector
6. Add Opacity filter and change its value by dragging it to the left

Actual results: Value goes to negative and no changes are made visually
Expected results: Value goes no lower than 0

Reproducible with versions: 6000.3.0a1
Couldn’t reproduce with versions: 2021.3.52f1, 2022.3.62f1, 6000.0.52f1, 6000.1.9f1, 6000.2.0b7 (no Filter section)

Tested on (OS): Ubuntu 22.04, macOS Sequoia 15.4 (M4)

Note: Issue is also reproducible on Invert, Grayscale, Sepia and Contrast filters as well