The element selection window is empty until anything is typed into the search bar when adding an element in the Strip Custom Comonents list in Multiplayer Roles

Steps to reproduce:

1. Create a new Unity project using the Universal 3D template
2. Install the Dedicated Server package (com.unity.dedicated-server)
3. Open the Project Settings window (Edit > Project Settings)
4. Open the Multiplayer Roles tab in the Project Settings
5. Click the "+" button in the Strip Custom Components list to add a new element
6. Observe the opened element selection window

Actual results: The element selection window is empty

Expected results: The element selection window is either not empty or if its by design to be empty the "+" button should be deactivated

Reproducible with versions: 6000.0.70f1, 6000.3.11f1, 6000.4.0f1, 6000.5.0a9

Tested on (OS): Ubuntu 24.04, MacOS Silicon Tahoe 26.3

Notes:

• Elements appear when something is typed into the search bar, for example "a"