Fixes the issue where the Enter key doesn't submit the WooCommerce login form when user registration is disabled. Temporary workaround until WooCommerce 9.9.9 (June 2, 2025).

fix-login-enter-key-woocommerce.php

/**
 * Fix for WooCommerce login form Enter key not working when registration is disabled
 * This is a temporary fix until WooCommerce 9.9.9 is released (June 2, 2025)
 */
function fix_woocommerce_login_enter_key() {
    // Only add this script on pages that might have the login form
    if (!is_account_page() && !is_checkout()) {
        return;
    }
    
    wp_add_inline_script('woocommerce', '
        jQuery(function($) {
            // Target all password inputs in login forms regardless of #customer_login existence
            $(".woocommerce-form-login .password-input").on("keydown", function(event) {
                if ("Enter" === event.key) {
                    $(this).closest("form").find("[type=submit]").click();
                }
            });
        });
    ');
}
add_action('wp_enqueue_scripts', 'fix_woocommerce_login_enter_key', 99);