I use Gnome (mostly) and KDE (rarely). I'm not familiar with Mate; I don't know
what a "panel meny" is. But no, you don't need to reboot.
Regardless of which user name I log in as, I launch xeyes from ".bash_profile",
and put it into the background. This way, the xeyes process and display is associated
with the login and root window (is that the correct term?) rather than any regular window
or process. The xeyes remain until I log off. I have a dual monitor system, so I
actually launch two xeyes: one on each monitor. Here are the ".bash_profile"
lines I use:
---------------
/usr/bin/xeyes -geometry 300x300+2259+0 -fg black -center pink -outline black &
/usr/bin/xeyes -geometry 300x300+2560+0 -fg white -center black -outline red &
---------------
The first puts an xeyes in the upper right corner of the left monitor; the second puts an
xeyes in the upper left corner of the right monitor. Both xeyes follow the cursor no
matter which monitor it's on. You can launch as few or many xeyes as you want, and
put them where ever you want. Type the command "xeyes ?" for more information
on command line parameters and options.
I hope that helps.
Bill.