On Tuesday 08 December 2015, Lisi Reisz wrote:
> > It should be on the Settings menu.  Or you can right-click on any menu
> > item and select Edit Item (or Edit Menu).
>
> Thanks!!  I could have sworn that I had looked in the Settings menu,
> several times, but it is indeed there.  Right click does not give Edit
> Menu, just edit item.
> But I still haven't managed to add an icon to the new menu entry.  It's odd
> that the Thunderbird tarball did not create a menu item with an icon. :-/

I just tested it by myself. I find some strange behavior. If you press the 'edit item' entry you are 
in the TDE Menu Editor. There is a a little square on the right upper side of the window. If you 
press it, the Select Icon menu appears. What now is strange that I can chose some icons that work 
(I really get a new icon in the menu) but for other icons I chose, nothing changes. 

Maybe test a few of those icons available to see if it is the same problem.

Gerhard