Fixes Rollback Auto-Update scraping when `home_url('/')` is redirected.

fix-rau-scrape-redirect.php

<?php
/**
 * Fix Rollback Auto-Update scrape for home_url redirect.
 *
 * @package Fix_RAU_Scrape_Redirect
 *
 * Plugin Name:       Fix Rollback Auto-Update HomeURL redirect
 * Plugin URI:        https://gist.github.com/afragen/494f5674ab18947a865c12d94f76155d
 * Description:       Redirecting the home URL can interfere with Rollback Auto-Update scraping. This fixes by adding the scrape query args when appropriate.
 * Version:           0.1.0
 * Author:            Andy Fragen
 * License:           MIT
 * Requires at least: 6.6
 * Requires PHP:      7.4
 * Gist Plugin URI:   https://gist.github.com/afragen/494f5674ab18947a865c12d94f76155d
 */

namespace WP_Upgrade_Install_Team;

add_filter( 'wp_redirect', __NAMESPACE__ . '\filter_wp_redirect', 10, 1 );

/**
 * Filters the redirect location.
 *
 * @param string $location The path or URL to redirect to.
 * @return string The path or URL to redirect to.
 */
function filter_wp_redirect( string $location ): string {
	if ( isset( $_REQUEST['wp_scrape_key'], $_REQUEST['wp_scrape_nonce'] ) ) {
		$location = add_query_arg(
			array(
				'wp_scrape_key'   => $_REQUEST['wp_scrape_key'],
				'wp_scrape_nonce' => $_REQUEST['wp_scrape_nonce'],
			),
			$location
		);
	}

	return $location;
}