Sohan Zaman

This Plugin will save your time by adding a duplicate button on each menu item while editing a menu. A real time saver. Currently it doesn\’t support customize screen, but I\’ll add it soon. If you find any bugs, just head over to support forum, I\’ll fix that asap.
Please rate me a 5 star if you find this plugin helpful 🙂

Nav Menu Item Duplicator

A simple plugin that adds a duplicate button to each items on edit menu screen.

TCBarrett

This plugin requires is just the front end javascript library, the following two things to be done in support: 
1. Add the class ‘simpleajaxform’ to your form. 
2. Make sure you have the correct wp_ajax handler hook defined.
It was primarily built as an example for a blog post.

Simple AJAX Form

A simple jQuery javascript library to ajax enable forms.

Nav Menu Item Duplicator vs Simple AJAX Form