I want to repurpose some old tablets as secondary displays. They're slow, but fast enough to run a VNC or RDP client. If I could set up some virtual/headless outputs that are accessible via VNC or RDP, I would find it very useful, because I could use any old tablet to extend my screen real estate. Gnome and Sway can already do this, and so can KWin with X11: - Sway has had an option to configure headless outputs since 2020, you can then run a VNC server on those outputs: https://www.reddit.com/r/swaywm/comments/k1zl41/thank_you_devs_free_ipad_repurposed_as_a_second/, https://github.com/swaywm/sway/issues/5553 - Gnome has support for virtual monitors via RDP since Gnome 42, support was merged a few months ago: https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/merge_requests/69 - With KWin X11 I used to be able to achieve this in a hackish way by setting up a virtual output in XRandR, similar to this: https://askubuntu.com/questions/28608/how-do-you-use-an-android-tablet-as-a-second-display.
Kwin also has support since 5.25
Thank you! That's great information.
I just upgraded to Plasma 5.25, so are there instructions somewhere on how to enable it? I didn't see anything that looks relevant when going through System Settings.
I have been trying to find a way to use this feature, are there any guides on how to set it up?
It appears the way to do this is with the `krfb-virtualmonitor` program, so Krfb needs to be installed, and what you do is you run `krfb-virtualmonitor --name WirelessDisplay --resolution 1920x1080 --password pAsSwOrD --port 5900` (change the resolution, port and password as needed), then with your phone/tablet/whatever you can connect to your system using a VNC client (on Android you can try bVNC for example, but just about any should work). You'll also need to know your system's IP address, I think that is shown in the Plasma System Monitor, and you need to make sure whatever port you pick is allowed through your system's firewall if you have one. Also, I think that might only work on Wayland, never tried it on X11 but I know it uses PipeWire.