How to reproduce:
1. Open the attached project "MPPMUIIssue-2023.1.zip"
2. Open Window>Multiplayer Play Mode
3. Enable "Player 2"
4. Enter Play Mode
5. Click the "CLICK ME" button in the "Player 2" Game view window
Expected results: The button is clicked
Actual results: The button is not clicked
Reproducible with: 2023.1.0b1, 2023.1.14f1
Not reproducible with: 2023.2.0a1, 2023.2.0b11, 2023.3.0a6
Could not test with: 2021.3.30f1, 2022.3.10f1 (not supported by MPPM)
Reproducible on: Windows 11 22H2
Not reproducible on: No other environment tested