I am running (trying to) Linux Mint 19.2 (Ubuntu 18.04) with an RX 5700 and have two AOC 24G2U monitors connected via Display Port.
I have loaded the recommended AMDGPU drivers. Only one monitor is active.
Under System Settings | Display a single monitor is identified as a laptop display.
Are there setup requirements for the Rx 5700 and how can I access them?