Game runs on Cry Engine V, I've tried the usual setting r_width/r_height and the game initially launches in ultrawide mode then forces itself into window mode at 2560x1440.
The console appears to be disabled so I can't set it ingame either to force it.
Hex edit Cuscene Aspect ratio: Go to ...\Far Cry 5\bin\FC_m64.dll Go to OFFSET 3F867A0 look for 00 00 10 41 and change it to 00 00 40 40 . Before: FarCry5 2018-04-22 21-29-11-41.jpg After: c4.jpg
and zens anticheat fix:
Search: " 40 55 53 56 57 41 56 48 8D AC 24 B0 FD FF FF" and change it to ...