Baseline (Widescreen) Solution & Issues
Widescreen in supported, but the FOV slider will need to be set manually. Assuming baseline is 16:9 and 90 degrees, then 16:10 needs to be 84 degrees. Otherwise, 16:10 is "Vert+". The FOV slider only goes down to 80 degrees, and that isn't low enough for 5:4 or 4:3.
The game does offer borderless window option.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
The FOV slider goes high enough for 21:9, but all the menu buttons and HUD are cut off.
Eyefinity / Surround Specific Solution & Issues
Unreal Engine Game (and all that entails)
The game natively supports the Eyefinity/Surround resolutions. The game has an FOV slider. The base for 16:9 is 90 degrees. The slider only goes to 110 degrees; however Eyefinity/Surround needs 151 degrees. So, the game is horribly Vert-. And, the menus are cut-off and broken. There is a HUD variable under [Enginer.HUD] in ForgeGame.cfg, but it doesn't do anything. There are also FOV variables in the cfg files, but they don't do anything above 110.
4k UHD Specific Solution & Issues