To reproduce:
1. Open user's attached project "New Unity Project (2).zip"
2. Build and Run for Android or iOS.
3. Expand and select any item fro any dropdown buttons
4. Without defocusing, select any of the remaing dropdown buttons

Expected: highlighted color is removed from the first dropdown button as it is no longer focused
Actual: highlighted color remains on the first dropdown, possibly due to event system not registering the change of focus

Reproduced in: 2017.4.16f1, 2018.2.17f1, 2018.3.0b11, 2019.1.0a9

Note1: on all LTS releases including latest 2017.4.16f1, clicking on dropdown makes the app stuck as defocusing is no longer possible which prevents the app from receiving input until restarted
also, multiple list items can be selected as the dropdown does not close upon selection

Note2: 2019.1.0a9 produces "Unity failed to extract resources needed by IL2CPP" on launch (see case 1100652)