Ultrawide aspect ratio and resolutions not available

[_Spectra_]

Hi all,
I recently picked up a shiny new ultrawide monitor. It's working fine on every other game I've tried that's meant to support it, but for some reason C:S isn't listing the 21:9 aspect ratio or resolutions in the graphics options.
You can see what I mean in the attached image. I've googled around but to no avail - I can't find anyone else having the same problem.
Possibly of relevance is that I have a secondary 16:10 monitor sitting off to the left. I'm running an RTX2070 with the latest drivers.
Any help would be greatly appreciated.

 

[AndrewT]

The resolutions shown in the game are the only ones it supports; remember the game is over 5 years old, well before ultrawide was a thing!

You can try forcing it with Unity launch options:
-screen-width XXXX -screen-height YYYY
but I doubt they will do it for you. Sorry about that!