Steps to reproduce:

1. Open a Unity Project
2. Create a new UI Document asset via Create > UI Toolkit > UI Document
3. Open the new UI Document in UI Builder by double clicking on it
4. Drag a Slider (Int) control onto the canvas
5. Select the SliderInt and set the Value to another value
6. Unselect the SliderInt by clicking elsewhere
7. Save the UI Document with File > Save

Actual results: The visible value on the SliderInt resets to a default value. You have to click on the control for it to go back to the value you set.

Expected results: The visible on the SliderInt remains at the value you set it to be.

Reproducible with versions: 6000.1.0a6, 6000.0.30f1, 2023.2.0a9

Not reproducible with versions: 7000.0.0a11, 2023.2.0a8, 2021.3.45f1

Can’t test with versions: 2022.3.53f1

Tested on (OS): Ubuntu 24.04, Windows 11

Notes: 

• In the most up-to-date versions, this only affects the Slider (Int) and not the normal Slider. However, it used to occur on the normal Slider too, which makes me think that at some point it was fixed for the normal Slider but the Slider (Int) was missed. 
• Can not test in 2022.3.53f1 as the Value field doesn't show up in the UI Builder Inspector for both Slider types. This might be another bug