The “Add icons…” button does nothing when clicked in the App UI - Icon Browser window

Steps to reproduce:

1. Create a new Unity project using the Universal 3D template
2. Install the App UI package (com.unity.dt.app-ui)
3. Open the Icon Browser window (Window > App UI > Icon Browser)
4. Create a new App UI Icons style sheet
5. Click the "Add icons..." button
6. Observe the Icon Browser window

Actual results: Nothing happens

Expected results: A window pops up to select icons

Reproducible with versions: 2.1.10 (6000.4.0a2, 6000.4.10f1, 6000.5.0b11, 6000.6.0a6)

Not reproducible with versions: 2.1.10 (6000.0.76f1, 6000.3.17f1)

Can’t test with versions: 2.1.10 (6000.4.0a1)

Tested on (OS): MacOS Silicon Tahoe 26.3