GUI: add multi monitors support
Multi monitors support requires a real windows for moving between monitors, but xmage GUI uses single app window/frame for all GUI elements. So it’s impossible with current GUI (java’s swing library).
Possible solution: duplicate and detach some panels into independent windows (simple use case - duplicate whole game panel with all elements, so user can move it into another monitor and setup as it wants, e.g. olen some panels with additional info/zones).
FYI - I run the window on a second screen, and whenever I open "Preferences", it pops up on the laptop screen, not the second screen with the rest of the game. (I believe the same is true for error messages and disconnection messages.)