Adaptation from Anachron's original block to my computer laptop acer aspire one.

display.sh

#!/bin/bash

xrandrOut=$(xrandr)

vgaName=$(echo "${xrandrOut}" | grep -i 'VGA' | awk '{print $1}')
lvdsName=$(echo "${xrandrOut}" | grep -i 'LVDS' |2 awk '{print $1}')

activeDisplays=$(echo "${xrandrOut}" | grep " connected" | sed -e "s/\([A-Z0-9]\+\) connected.*/\1/" | tr -s '\n' ' ')
displayFile='/tmp/.displays'

if [[ -f "${displayFile}" ]]; then
    oldDisplays=$(cat "${displayFile}")
else
    oldDisplays=""
fi

if [[ "${oldDisplays}" != "${activeDisplays}" ]]; then
    change="yes"
else
    change="no"
fi

# External, HDMI + VGA
if [[ "$activeDisplays" =~ "${vgaName}" ]]; then
  if [[ "${change}" = "yes" ]]; then
    $(xrandr --output "${lvdsName}" --primary --auto)
    $(xrandr --output "${vgaName}" --auto --left-of "${lvdsName}")
    $(feh --randomize --bg-fill /home/user/.wallpapaers/*) #set different wallpapers to vga and lvds1. 
    #checking if is there any option to enable just one wallpaper to both displays.
  fi
  echo "VGA"
  echo "VGA"
  echo ""

# Only one internal
elif [[ "$activeDisplays" =~ "${lvsdName}" ]]; then
  if [[ "${change}" = "yes" ]]; then
    $(xrandr --output "${lvdsName}" --primary --auto)
    $(xrandr --output "${vgaName}" --off)
  fi
  echo "LVDS"
  echo "LVDS"
  echo ""
  
fi

if [[ "${change}" = "yes" ]]; then
  echo "${activeDisplays}" > "${displayFile}"
fi