Click for mouse control only works on last client. Mouse is not catched in the window of the other clients but you have to hold down left mouse-button (which is bad in a running game if this is your fire button).
Steps to reproduce:
Create a third person template:
Start with 2 clients: Alt-Tab between the Client-windows: Click for mouse control only works on window of client 2
Start with 3 clients: Alt-Tab between the Client-windows: Click for mouse control only works on window of client 3
I was able to reproduce this issue on our end. I have written up a report (UE-28378) and I have submitted it to the developers for further consideration. I will provide updates with any pertinent information as it becomes available. Thank you for your information and time.
I was able to reproduce a similar issue in the latest version of the engine. However, I was not able to reproduce the original issue mentioned on the thread. I have written up a new report for the issue that I found. I have provided links for the public tracker for both issues. Please feel free to use the links provided for future updates.