> So just forget about
>> the idea of adding a file menu to the toolbox. The toolbox is not a
>> normal toplevel window any longer, it's just a utility window for the
>> active image window.
> Sorry, I'm not going to "forget about it". I want it back the way it was -
> with the File menu at the top of the toolbox window, the toolbox window
> behaving as a normal toplevel window, and no default blank image window. It's
> much more convenient that way.
There is no way to get the menu back and no such way is going to be
added. The only way to get a menu in the toolbox is to use GIMP 2.4.
There were many reasons to get rid of the toolbox menu, one being that
two menubars in one application is just plain wrong. For more reasoning
behind the change, refer to the UI specification 
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