Text "Outline Width" and Bold "Front Style" are not shown in the Text Property Preview window in UI Builder when the Text Size is smaller than 19px

Steps to reproduce:

1. Create a new Unity project using a 3D Universal Template
2. Go to Assets > Create > UI Toolkit > UI Document
3. Open the created .uxml in UI Builder
4. Create a new USS file by clicking the "+" button in StyleSheets tab
5. Add a new selector
6. Select the created selector
7. In the Inspector, expand the Text foldout
8. Change the "Outline Color" to any bright color (for better visibility)
9. Increase the "Outline Width" value
10. Observe the Text Property Preview window

Actual results: The outline is not visible in the preview window

Expected results: The outline is visible in the preview window

Reproducible with versions: 2023.1.0b1, 6000.0.64f1, 6000.2.15f1, 6000.3.1f1, 6000.4.0b1, 6000.5.0a3

Reproducible on: Windows 11
Not reproducible on: macOS 26.1 (M1 Pro)

Notes:

• Issue also reproduces with "Font Style" Bold property
• This issue only affects the preview, as the outline is shown correctly on the actual text
• The outline is shown correctly in the preview if the Text Size is above 18px