Steps to reproduce:

1. Create or open any Project
2. In the Project Browser right click and choose Create > TextMeshPro > Style Sheet and select it
3. Click the + button in the Inspector to add an entry
4. Click the Down button until the last item is selected and then click it once more

Actual results: The Down and Up buttons will highlight other elements in the Inspector other than the Style entries in the list when they are disabled.

When the last item in the list is already selected and the Disabled Down button is pressed it will unselect the last item, the same will happen with the Up button when the first item in the list is selected

Other disabled buttons also unselect the already selected Item

Expected results: None of the Buttons in the Style Sheet's Inspector do anything when they are disabled

Reproducible with versions: 2023.1.0a1, 6000.0.71f1, 6000.3.12f1, 6000.4.1f1, 6000.5.0b1, 6000.6.0a1

Tested on (OS): Windows 11

Notes:

• Same issue is present in the Text Core Style Sheet