separate browser to own linux user

gistfile1.sh

# a is your username

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# as root
adduser b
usermod -a -G b a
chmod 770 ~b
# chmod 700 ~a # if you want/need

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# to /etc/sudoers
a       ALL=(b) NOPASSWD: /usr/bin/yourcmd1
a       ALL=(b) NOPASSWD: /usr/bin/yourcmd2

 ###############################################
# executable/shellscript - br.sh
# usage: br.sh <username> <command> [command params]

USER=${1}
shift 1
xhost +si:localuser:$USER
sudo -u $USER -g $USER "${@}"
xhost -si:localuser:$USER

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# optional, to your .[a-z]{1,2}shrc - if you
# use only one user
alias br 'br.sh b'