Remove duplicate feed items via titles.

feedzy-remove-duplicate-via-titles.php

<?php
/*
Plugin Name: Feedzy tweak - Remove duplicate feed items via titles
Description: When you have a large set of feed URLs that you would like to display. Use this plugin to remove the duplicates based on their titles.
Version: 0.0.1
Author URI: https://themeisle.com
*/
function tifd_feedzy_remove_duplicates( $items, $feedURL ) {
	$uniques = array();
	foreach ( $items as $item ) {
		if ( isset( $uniques[ strval( md5( $item->get_title() ) ) ] ) ) {
			continue;
		}
		$uniques[ md5( $item->get_title() ) ] = $item;
	}
	return array_values( $uniques );
}  
add_filter( 'feedzy_feed_items', 'tifd_feedzy_remove_duplicates', 10, 2 );