OK sorry, I'm necroing this thread to update on the current version, since sometime around the introduction of 21:9 resolutions this work around hasn't worked. If I want to play in fullscreen I HAVE to use one of the resolutions hard coded into the game (again restricting resolutions rather then providing the list pulled from the graphics drivers is unacceptable in my book).
You can still play at these resolution but you will need to run in Fullscreen Boardless Window mode, same FoV fix works, but be aware the HUD is now scaled based on the horizontal resolution, with no limit in place. Meaning the HUD is 3x the size it should be, at least it appears to be positioned correctly (spanned to the edge of the side screens but it used to all be on the left screen).
Devs: Please stop restricting the resolution people can play you game at, I get you don't have the time to add in proper multi-monitor support yet but that's no excuse to stop us from trying to get it to work on our own. I shouldn't have to jump though hoops to have my games running at my desktops native resolution.
Second, you can fix the scaling issue on the HUD by scaling it by the height rather then the width of the screen, this is a much better approach since people tend to have wider monitors, not taller, and when scale up from 1080p to 4K the scaling between height and width is the same since both are 16:9 aspect ratio.
Edit: I've not played around with UE4 so I don't know how much use the following is, but:https://docs.unrealengine.com/latest/IN ... index.htmlhttps://wiki.unrealengine.com/Get_Avail ... Blueprintshttps://wiki.unrealengine.com/index.php ... esolutions