How to reproduce:
1. Create and open a new project
2. Install the “com.unity.dt.app-ui” package
3. In the project window create a new asset: AppUI/App UI Settings
4. Select the asset and in the Inspector window click on the Help “?” icon
Actual result: A missing documentation page is opened
Expected result: An existing documentation page is opened
Reproducible with: 1.3.3 (6000.0.65f1), 2.2.0-pre.3 (6000.0.65f1, 6000.4.0b3, 6000.4.0b3, 6000.5.0a4)
Reproducible on: macOS Tahoe 26.1
Not reproducible on: no other environments tested
Note: This also reproduces with APP UI Navigation Graph asset