Add recurring-all class to /all/ page

recurring-all.php

<?php

add_filter( 'body_class', 'tribe_recurring_all_body_class', 10, 1 );

function tribe_recurring_all_body_class( $classes ) {
	if ( function_exists( 'tribe_is_showing_all' ) && tribe_is_showing_all() ) {
		$classes[] = 'recurring-all';
	}

	return $classes;
}