A sidebar menu that supports nested lists where the nested items are displayed only if the user is in that group.
Add the following line to local/config.php:
Decorate your existing sidebar menu with
From the technical point of view,
It does not affect any other lists outside
Example (copy and paste to your page, it won't work here)
In this example, when the user is on any page in the Main group, only the first three items in the menu are displayed. When the user is on any page in the PmWiki group, all the menu items are displayed.
See discussion at ExpandingMenu-Talk