If you see the same thing on both displays, you should start by making sure the displays are Extended instead of Mirroring ...

Setting up dual monitors with XRandR can be a straightforward process once you understand the basics. Here’s a step-by-step guide to help you configure your dual-monitor setup using XRandR ...

The ability to have two or more external monitors connected to your Mac in Extended Mode is a liberating screen experience, but leads to frustration when each still operates like an independent ...