Change Continue Shopping link to the Previously Visited Page in WooCommerce

functions.php

<?php

// =========================================================================
// Changes the redirect URL for the Return To Shop button in the cart.
// =========================================================================
function wc_empty_cart_redirect_url() {
    if( WC()->cart->is_empty() )  {
        return wc_get_page_permalink( 'shop' );
    } else{
        return $_SERVER['HTTP_REFERER'];
    }
}
add_filter( 'woocommerce_return_to_shop_redirect', 'wc_empty_cart_redirect_url' );