Thanks for the reminder.
I will put it on my list. Now finishing a contents browser. So that we can remove all the codeHolder hierarchy finally.
There is DockingBarMorph, for example:

|d|
"World deleteDockingBars."
d:=
������ DockingBarMorph new.
������ World worldMenu items copy select:[:i| i hasSubMenu] thenDo:[:i|
������ ������ d
������ ������ add: i contents
������ ������ icon: i icon
������ ������ help: i contents
������ ������ subMenu: i subMenu].
������ d������ adhereToTop;
������ openInWorld.


Although this does not work at the moment due to issue
14829
Spec MenuModel submenu not working