Re: address@hidden: Customizevaluemenudoesn'trecognizemouse-2]

[rms]

    That GUI applications don't do that.  So, unless we let mouse-2 drop
    menus from the menu bar on other platforms as well (personally, I
    think we shouldn't, certainly not at this time), I'd object to do that
    only on Windows.

On my platform, all three mouse buttons work to activate a menu bar menu
in Emacs.