UIToolkit property field background does not change color when the property is animated

How to reproduce:
1. Open the project “IN_29005”
2. Open the "test-animated-prop-ui" Scene
3. Open the Animation window
4. In the Hierarchy click on "Gameobject"
5. In the Animation window press the “Play the animation clip”
6. In the "Custom Component" properties in the Inspector observe the input field below the "UIToolkit property field"

Expected result: the background colour of the “Animated value” changes (to blue or red)
Actual result: the background colour of the “Animated value” does not change

Reproducible with: 2020.3.43f1, 2021.3.17f1, 2022.2.4f1, 2023.1.0b1

Reproducible on: Windows 10 Pro