Baseline (Widescreen) Solution & Issues
This game supports widescreen out of the download. On the loading screen, there is an "Options" button. Click that and select your resolution.
Of Note: I had a problem with changing resolutions when in full-screen (non-windowed) mode. The screen would simply blank out. If I killed the game, went back in, selected Windowed mode (restarted), and the changed resolutions, it would work. This was a bug for any resolution change, whether widescreen or narrowscreen.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues