Add/Modify Google tag manager variables for Rank Math SEO

gtag.php

<?php
if ( ! function_exists( 'prefix_analytics_gtag_config' ) ) :

    /**
     * Add/Modify Google tag manager variables
     * 
     * @param array $args   Google analytics arguments
     */
    function prefix_analytics_gtag_config( $args = [] ) {

        $args[] = 'cookie_flags:"max-age=7200;secure;samesite=none"';

        return $args;
    }
    add_filter( 'rank_math/analytics/gtag_config', 'prefix_analytics_gtag_config' );

endif;