WooCommerce Checkout Troubleshooting: Find the Failing Layer

When a WooCommerce checkout fails, changing several plugins at once makes the cause harder to identify. Work from the browser request toward the server and payment provider in a repeatable sequence.Record the exact symptom: a spinner that never ends, a validation message, a failed payment, or an order that exists despite an error. Check WooCommerce logs and PHP error logs for the same timestamp. I...