'Adaptive icons', 'Round icons' & 'Legacy icons' dropdown buttons under icon-Settings for Android do not respond when clicked on their header name. These dropdown buttons have to be clicked on the dropdown arrow specifically. Refer the attached video

Steps to reproduce:
1) Create a new project
2) Build Settings > Android > Switch Platform
3) Build Settings > Player Settings > Settings for Android
4) Click on 'Adaptive icons', 'Round icons' & 'Legacy icons' header names.

Actual result:
Under icon-Settings for Android, dropdowns buttons do not respond when clicked on their header name.

Expected result:
On clicking header names it should be highlighted and dropdown should open.

Reproducible in:
2021.1.0a5, 2020.2.0b11, 2020.1.12f1, 2019.4.14f1, 2018.4.28.f1

Environment:
Windows10 and macOS 10.15