"No RANDR extension" was the result of clicking "nvidia-settings" (installed automatically by Ubuntu installer) to use external monitor as "separate X screen" with "xinerama", no need to open a terminal to get into this.
"No RANDR extension" was the result of clicking "nvidia-settings" (installed automatically by Ubuntu installer) to use external monitor as "separate X screen" with "xinerama", no need to open a terminal to get into this.