I apologize if this isn't the place to list this issue.
The documentation for the Menu class lists information about the before variable which states:
Insertion position constants Used by addMenu(), addMenuItem(), and addSubMenu() to specify the relative position of a newly created menu object
However, there is no functionality as of yet for addSubMenu()

I apologize if this isn't the place to list this issue.
The documentation for the
Menuclass lists information about thebeforevariable which states:However, there is no functionality as of yet for
addSubMenu()