Anonymous
Hello,
This can be changed via an Xorg configuration file
That summarizes it all.
The ways it is implemented, one can create a file e.g. 10-monitor.conf in /etc/X11/xorg.conf.d/ and setup accordingly.
I have used: Two “Section “Monitor””, One “Section “Device””, Two “Section “Screen””.
Within Section Monitor, the block related to VGA external monitor, add “Option “Disable” “true”” and comment out or remove the line “Option “PreferredMode” “XxY””, otherwise it will override the former.
Obs: X is horizontal pixels and Y, vertical.
On the other hand, “Option “Enable” “false”” might work instead.
Remove first and last quotes from the triggering compound sentences (configuration parameters).
Then is suggested to add in desktop-session’s startup, a xrandr command to deal with dual monitor setup.