A debian user noticed that when xfce-mcs-manager was refreshed (pkill -USR1 -f
xfce-mcs-manager) the weather plugin crashed. Gdb output isn't really useful
(i've attached it, though).
On debian, we use to refresh xfce-mcs-manager each time a new component is
added/upgraded/removed so it is in a consistent state with the system. So when
there is a system upgrade, the weather plugin disappears from the panel.
Steps to Reproduce:
1. add xfce4-weather-plugin in the panel
2. pkill -USR1 -f xfce-mcs-manager