Xinerama can be enabled but has been deprecated for a long time now (circa before I built said desktop). If you do decide to use it, you'll have to learn to live with the many problems and bugs that comes with using something that hasn't been updated in years.

> This constant regression in features is what I dislike most about Linux lately. Eternal September in software form.

This is what pushed me from using Linux full time for almost a decade to jumping ship to Apple a year ago. That and people like AsyncAwait who never seem to respond to people like me who post concrete real world problems despite claiming everything negative is FUD.