alpipego

This plugin makes long and complex navigation menus better manageable by creating groups that can be expanded and collapsed.
By default, all navigation menus in wp-admin will be collapsed. When holding the Option/Alt-key while clicking, all sublevels will be expanded with one click.
For general support, please use the support forums on <a href="https://wordpress.org/support/plugin/wield-menu" rel="ugc">wordpress.org</a> 
For developers: Head over to the <a href="https://github.com/alpipego/wield-menu/" rel="nofollow ugc">Github repository</a> 
For everything else, find me on <a href="https://twitter.com/alpipego" rel="nofollow ugc">twitter</a> or slack

Wield Menu

I had this problem when working on themes demo as they have all possible page in the menu.

Thanks!

Very handy

Make long and complex Navigation Menus wieldable

WP-EXPERTS.IN

A smart way to display child menu items in the widget sidebar. The Menu-Based Sidebar plugin provides an option to display child menu items in the sidebar based on the currently selected parent menu item.
<h4>Features</h4>
 * Shortcode [mbs_menu menu_id=”MENU_ID_GOES_HERE”] 
 * Display menu items in sidebar on based current main menu item 
 * Auto display child pages on based of current main menu item
<h4>Note: If you are using any cache plugin on your website then please clear site cache after enable/update plugin settings</h4>
Please don’t forget to leave your valuable feedback and suggestions to make our plugin much better compared to other plugins.
 <a href="mailto:raghunath.0087@gmail.com" rel="nofollow ugc">Have you any suggestion? share it</a>

Menu Based Sidebar

Displays child menu items in the sidebar based on the currently selected parent menu item.

Wield Menu vs Menu Based Sidebar