There are many threads about how to restore the dropbox icon. For instance, this link.
Following those instructions in xubuntu 18.04 restores the menu icon, but left or right clicking the icon just brings up a useless, empty menu. Specifically, running the following in a terminal brings me to this state:
dropbox stop
env XDG_CURRENT_DESKTOP=Unity dropbox start
I'm aware that on xubuntu Unity is not the desktop. Running
echo $XDG_CURRENT_DESKTOP
returns XFCE, but replacing XDG_CURRENT_DESKTOP=Unity
by XDG_CURRENT_DESKTOP=XFCE
brings the dropbox back to a broken state where the normal dropbox icon doesn't appear at all.
Any thoughts on what to do?