Prevent Permalink Manager to redirect the current URL to the current URL.

gistfile1.txt

<?php

// exit if accessed directly
if ( ! defined( 'ABSPATH' ) ) exit;

add_filter('permalink_manager_filter_redirect', function($correct_permalink, $redirect_type, $queried_object) {
	$relative = wp_make_link_relative($correct_permalink);
	$old_uri = wp_make_link_relative($_SERVER['REQUEST_URI']);
	if ($relative == $old_uri) {
		return '';
	}
	return $correct_permalink;
}, 10, 3);