Linux – Use X desktop apps using another users on the own account, like with root

desktopdisplaylinuxrootuser

It's possible run apps from command line like root using "su root" , and later executing the app, like firefox, and works, using the data from root home. But why I can't do it with another users using "su user" ? The rest trow me one error: " No protocol specified . Cant open display"
Thanks you.

Best Answer

Yo will have to allow the new user to access your X server.

     xhost +

must be issued before su name_of_2nd_user.