Despite the fact there is more than enough room on my screen, Firefox page-right-click menu usually appears pretty small and offers vertical scrolling to view all the items inside it. Some times the effect is like the opposite - a huge free space area is added to the menu after the items. This seems like a problem with XUbuntu (or XFCE). Any experience fixing this?
Example (note the arrow boxes on the top and on the bottom):
xfwm4
.