If the order received (checkout thank you) page is viewed after an order has been marked pending payment, the pay and cancel buttons will show. There is no gap between them. On small mobile, they are stacked with no gap between them. This can’t be styled with the panel on the checkout-thank-you template.
The rest is not technically a bug, but there are other buttons that may show and there is no syle for them in the builder panel. They are not hard to style for me, just pointing it out.