Creating Monitors on Unused Ports

[Shakil Shaikh]

I'm trying to get my host's display :0 to render more monitors than are connected. This is for remote access purposes[1]. Here's my default xrandr output:

Screen 0: minimum 320 x 200, current 1024 x 768, maximum 16384 x 16384
VGA-1 connected primary 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768      60.00*
   800x600       60.32    56.25
   848x480       60.00
   640x480       59.94
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)

The closest I've come to achieving what I'm after is with the following minimal config (I can add further modes if required).

########
Section "Monitor"
    Identifier "VGA-1"
    Option "Ignore"
    Option "Enable" "false"
EndSection

Section "Monitor"
    Identifier "HDMI-1"
    Option "Enable" "true"
    Option "Primary"
EndSection

Section "Monitor"
    Identifier "HDMI-2"
    Option "Enable" "true"
    Option "LeftOf" "HDMI-1"
EndSection
########

The xrandr output is now:

#########
Screen 0: minimum 320 x 200, current 2736 x 768, maximum 16384 x 16384
HDMI-1 disconnected primary 1368x768+1368+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1368x768      59.88*
   1280x800      59.81
   1280x720      59.86
   1024x768      60.00
   1024x576      59.90
   960x540       59.63
   800x600       60.32
   800x450       59.82
   700x450       59.88
   640x480       59.94
   684x384       59.88    59.85
   640x400       59.88    59.98
   640x360       59.86    59.83
   512x384       60.00
   512x288       60.00    59.92
   480x270       59.63    59.82
   400x300       60.32
   320x240       60.05
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected 1368x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1368x768      59.88*
   1280x800      59.81
   1280x720      59.86
   1024x768      60.00
   1024x576      59.90
   960x540       59.63
   800x600       60.32
   800x450       59.82
   700x450       59.88
   640x480       59.94
   684x384       59.88    59.85
   640x400       59.88    59.98
   640x360       59.86    59.83
   512x384       60.00
   512x288       60.00    59.92
   480x270       59.63    59.82
   400x300       60.32
   320x240       60.05
##############

This appears to work well, but the only issue is that the Display Manager of my DE (KDE Plasma) kscreen doesn't think there are any monitors connected, which I suppose is reasonable enough. However arandr appears to detect the displays okay.

My questions then are:

1) Assuming this is an unsupported configuration, am I doing anything incorrect or even dangerous? 
2) I appreciate that KDE is outside the scope of Xorg, but what could be kscreen looking for? Can I provide it via the xorg config?

Thanks,

[1] I'm only able to get GL performance from my Intel P4600 IGD when accessing the host display. I've tried virtualGL and it didn't seem to be performant (possible due to my IGD being a lowly P4600). Nomachine does work, but only when set to "mirror" the host display. This is great, except I only have a VGA screen attached, and so can't set my desktop larger than that, even if my client screens (on a Windows machine) are much bigger.