If you are running a X11 based system, Linux et al, this should be trivial enough with existing tools.
Take the example here using VNC and xrandr
From a currently running X11 session, I would like to provide/run a VNC server such that it appears to my system as a second, “virtual” monitor – i.e. so that I can position it using xrandr and drag/
unix.stackexchange.com
Now connect via an html5 based vnc client like,
novnc.com
and for bonus points go full screen using the tesla youtube hack. If you find the following video, or create your own with appropriate link in the description,
via the youtube app on the tesla main screen then follow the vnc links to the vnc web app. Youtube runs full screen and any links followed also run full screen, (also works as a proxy to run additional streaming services in full screen), you can then also make the vnc web app fullscreen by selecting the vnc web app fullscreen option.