Steps to reproduce:

1. Open a Unity project
2. Open the UI Builder via Window > UI Toolkit > UI Builder
3. In the Hierarchy, select the .uxml file so it shows the Canvas details in the Inspector
4. Observe the Canvas Background section

Actual results: The check box next to the 'Canvas Background' section header blends into the background, making is not very visible and hard to see (screenshot below makes it slightly easier to see than it is in reality)

!image-2024-07-25-11-37-32-181.png!

Expected results: The check box next to the 'Canvas Background' section header does not blend into the background, and is very visible

Reproducible with versions: 6000.0.13f1, 2022.3.40f1, 2022.1.0a10

Not reproducible with versions: 2022.1.0a9, 2021.3.40f1

Can’t test with versions: -

Tested on (OS): Windows 10. Windows 11

Notes:

• This issue only affects dark mode, not light mode where the check box is much more clear
• In Unity versions before the FAV, the check box was much more visible, as shown here: 

!image-2024-07-25-11-41-45-958.png!