OK, this so far appears to be a problem in appmenu-gtk, because it only re-examines the menubar when it sees new items inserted. So it correctly notices the first time any of these menus is created. But when just switching between menus that have already been created, it doesn't notice.
Probable fix is to make it watch when menubars are reparented.
OK, this so far appears to be a problem in appmenu-gtk, because it only re-examines the menubar when it sees new items inserted. So it correctly notices the first time any of these menus is created. But when just switching between menus that have already been created, it doesn't notice.
Probable fix is to make it watch when menubars are reparented.