UI Builder doesn't update the style sheet when using "Extract inline style" right-click option

How to reproduce:
1. Open the attached “IN-99171” project
2. Open the “SignUp Username” document in UI Builder
3. Select the “NextButton” in Hierarchy
4. In the UI Builder’s Inspector, scroll down to the Border section
5. Right-click Width > Bottom and select "Extract inline style to selector”, then choose “.confirm-button:disabled” and Save (Press CTRL+S)
6. Right-click on the same property again and select “Open Selector in IDE”
7. Observe the “.confirm-button:disabled“ style

Expected result: The “.confirm-button:disabled” style is updated and saved
Actual result: The “.confirm-button:disabled” style doesn’t change in the “Screens.uss” file

Reproducible with: 6000.0.49f1, 6000.1.3f1, 6000.2.0b1
Couldn’t test with: 2022.3.61f1 (Can’t right-click to “Extract inline style”)

Reproducible environments: Windows 10 (by reporter), macOS 15.4.1
Not reproducible environments: No other environments tested

Notes:

• If the style sheet is updated by “Extracting inline style to selector” and then the Editor is closed, the change does not persists when the Editor is reopened
• The style sheet does get updated some times by other methods, but inconsistently