filter-heartbeat.php

<?php
add_filter( 'heartbeat_settings', 'filter_heartbeat', 10, 1 );

/**
 * Filter the heartbeat interval based on the current request.
 *
 * Called on the 'heartbeat_settings' filter.
 *
 * @param array $settings The Heartbeat settings. By Default an empty array.
 *
 * Credits: Ideas used from https://wordpress.org/plugins/heartbeat-control/
 */
function filter_heartbeat( array $settings ): array {
	$request_uri = filter_var( $_SERVER['REQUEST_URI'], FILTER_SANITIZE_URL );

  if ( str_contains( $request_uri, '/wp-admin/post.php' ) ) {
		// In the editor.
		$interval = 60;
	} elseif ( is_admin() ) {
		// In the admin panel.
		$interval = 180;
	} else {
		// In the frontend.
		$interval = 3600;
	}

	$settings['interval'] = $interval;
	return $settings;
}