How to add submenu for plugin on left side

Elastic Stack Kibana
1

how to add submenu for plugin on left side?

2

Which version of Kibana? And can you provide some more details about what you are trying to do? I'm not sure what you're asking for when you ask about a submenu on the left side. Some screenshots or a sketch or something may help illustrate what you mean.

3

version kibana 5.0
as you know, one plugin can add one or more menu items on left side. but they are not nested. is there any way to add a nested menu for plugin? like below

menu1
menu2
-----menu2.1
-----menu2.2
menu3

4

any response about cascading menu?