Add Logged-In Body Class on Frontend

WordPress adds logged-in to the body when a user is logged in, but only in the admin. The following code adds a class on the frontend too. Useful for custom styling or showing different content. For more on WordPress hooks and filters.

add_filter( 'body_class', function( $classes ) {
	if ( is_user_logged_in() ) {
		$classes[] = 'logged-in-user';
	}
	return $classes;
} );