[Latinyanin]

Решение

Код:

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
@namespace html url("http://www.w3.org/1999/xhtml");
menu.bookmark-item, menuitem.bookmark-item {
max-width: 11em !important;
}
menu#edit-menu, menu#view-menu {
    display: none !important;
}
#main-menubar > menu {
    -moz-box-ordinal-group: 1000 !important;
}
#main-menubar > menu#file-menu {
    -moz-box-ordinal-group: 0 !important;
}
#main-menubar > menu#history-menu {
    -moz-box-ordinal-group: 1 !important;
}
#main-menubar > menu#tools-menu {
    -moz-box-ordinal-group: 2 !important;
}
#main-menubar > menu#bookmarksMenu {
    -moz-box-ordinal-group: 3 !important;
}
#main-menubar > menu#helpMenu {
    -moz-box-ordinal-group: 6 !important;
}