The Xfce panel's right click menu seems to be serving several master, leading to
some minor usability issues.

On my (admittedly somewhat stale) SVN build of the panel, the ordinary context
menu looks like this:

Xfce Panel
----------
Add new item
----------
Properties...
About Xfce
Help
----------
Lock screen
Restart
----------
Exit

Some of this functionality is misorganized (why are panel restarts and lock
screen together?), some of it is ambiguous (restart and exit are both in the
menu, but one restarts the panel alone, the other attempts to exit the desktop),
and some of it is inconsistent (Exit exits Xfce, in the standard desktop menu,
the same entry is Quit, with an icon).

I would suggest a new menu that looks like this, ideally. Part of this is based
on assumptions about the panel's future feature set.

Xfce Panel
----------
Help
Remove this panel
Settings
Add new item

First off, the various locking and exiting functions are removed because they
are already available as panel plugins, and also in the menu, which can now be
pushed into the panel. Secondly the Restart option has been removed with the
hope that out of process plugins and general panel rearchitecting will remove
the need to manually tell the panel new plugins are installed. "About Xfce" goes
because Xfce is highly modular, and the panel can run without the desktop and
vice versa, and because it doesn't really belong in the panel menu (where it
belongs, I am not sure.)

"Add new item" of course remains, and performs the same function, although
perhaps it should add the item in the position marked by the context menu,
instead of defaulting to the end. "Add new item" is the bottom entry because in
most configurations of the panel (both in terms of what is possibile and user
tendency), the bottom position is the most quickly accessible, and "Add new
item" the most common action.

"Properties..." has been changed to "Settings" because the elipsis was unneeded,
and to be more consistent with the rest of the desktop (xfdesktop menu calls
them settings, and places the Xfce Panel MCS plugin under a "Settings" submenu,
the system button which pulls up the MCS panel is called "Settings"). It is
second from the bottom following the Gnome HIG which tries to order items in
terms of their likelihood of use.

"Remove this panel" is one of the rarer actions, and for safety's sake needs to
be difficult to accidentally hit. We specify that it is the panel we are
removing to kill any ambiguity between the panel itself and it's plugins, and to
make the functionality more discoverable. This assumes we get to multiple panels
by 4.4.

Help is of course the panel help, least accessed (probably once or twice), but
when the user needs it it needs to be prominently displayed, so it's the last item.

And, finally, the disabled "Xfce Panel" helps kill ambiguity, just as now,
between the panel and it's plugins.