I have a 3 monitor set up, with my middle monitor being my main one.
When I start Arma 3 Alpha, it starts correctly on my middle monitor, however when the menu loads my mouse is unable to highlight any of the menu or click anywhere.
If I then minimize the game using ALT + TAB or just clicking on a different monitor, the game minimizes and when I open it up again it puts itself on my far right monitor, and then the mouse proceeds to work like it should. I have tried restarting my computer and steam, if you guys have had any issues like this and have known solutions I am all ears!