So after a few weeks my wife had her first problem with the XFCE desktop, she came to me with a very strange problem… somehow the window borders on all XFCE desktop were gone !!!?!?!
Could this be a bug of some kind?
Anyway I went into the terminal and issues the following command
xfwm4 --replace &
e and immediatly the window borders came on!
We later found out, that waht causes the problem is that she closes the laptop with Firefox still on, instead of properly shutdown.