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Background: If you connect a 2nd monitor/projector by cable to a computer, you often can easy make the screen expand, so each monitor have there own area of the screen, and you can move windows between them. If the screen is far away, a network connection could be easier.
Question: If I want to connect a 2nd monitor/project by network/vnc, can I share an area outside the 1st monitors area? so I can move windows between them. How do I set up the screen size, and what area to share, in a VNC server?
Computers: VNC-server: running kubuntu, open for sugestion for what VNC server software to use. VNC-client: a rasbery-pi, runing Raspbian, and running xtightvncviewer in listening-mode