Makes the 'Merge Duplicates' button appear and stick in The Events Calendar

merge-duplicate-organizers-venues.php

<?php
/*
 * Description: Makes the 'Merge Duplicates' button appear and stick
 * under Events > Settings > General tab
 *
 * Plugins: The Events Calendar
 * Author:  Barry Hughes
 * Last updated: November 2, 2017
 */

add_filter( 'tribe_get_single_option', function( $value, $default, $key ) {
    return 'organizer_venue_amalgamation' === $key ? 0 : $value;
}, 10, 3 );