GTK 2.16 is required now.
Warnings during conversion:
[main_win:main_vbox:menubar:view_menu_item:view_menu:menu_item_view_arrange] Property 'Tooltip' of object class 'Widget' is only supported in libglade format
[main_win:main_vbox:toolbar:toolitem28:alignment2:hbox4:buffer_size_combo] Property 'Tooltip' of object class 'Widget' is only supported in libglade format
[main_win:main_vbox:toolbar:toolitem28:alignment2:hbox4:buffer_size_combo] Property 'Items' of object class 'Combo Box' is only supported in libglade format
[main_win:main_vbox:toolbar:clear_load_button] Property 'Tooltip' of object class 'Widget' is only supported in libglade format
[main_win:main_vbox:toolbar:toolitem30:alignment3:xrun_progress_bar] Property 'Tooltip' of object class 'Widget' is only supported in libglade format