The poster asks whether there is a console command or user.cfg entry to get around the disabled UI Scale slider, which stopped working around 3.24, because UI elements on a triple 32" monitor setup in the upper corners may cause neck strain.asked by Xypher_1210

Say no more, i've just fixed it for 4.0.1, you are welcome!
I've also fixed the mouse confinement in fullscreen mode with multiple monitors (mouse was moving onto other screens briefly before)
And last but not least the engine now fully supports playing the game in any aspect ratio on any monitor in fullscreen mode. This means it is possible to play with a widescreen aspect ratio on a 16:9 monitor if desired (i.e. with blackbars on the top and bottom)

As always, thanks for your patience and fly safe o7
Silvan