@AlexDeucher I am using xserver-xorg-video-amdgpu. I can use 18.0.1 (No TILE
support, need workaround) or 19.0.1 (Cinnamon crashes, need workaround for time
being). I'm looking for a xorg config or xrandr command that works like
nVidia's TwinView that I can keep in place while I am checking TILE support
with this DM and kernel from time to time. (I am new to AMD/Radeon.)

@TomasBzatek I still need a workaround because Cinnamon crashes on 5.2 w/
19.0.1 TILE support. See https://github.com/linuxmint/cinnamon/issues/8807