Removes the "Storefront" link from under the Appearance tab in your dashboard

storefront-remove-welcome-link.php

<?php
/**
 * Removes Storefront's Welcome page
 */
if ( ! class_exists( 'Storefront_Admin' ) ) :
	class Storefront_Admin {
		public function __construct() {
			remove_action( 'admin_menu', 'welcome_register_menu', 1 );
		}
	}
endif;
return new Storefront_Admin();