Shopify App Checkout Shipping Error Message Bug

[Hanson1]

I have found a bug in the frontend for the "https://shop.app/checkout" UI. For certain stores, when the shipping is calculating, an error message appears temporarily and then disappears after the shipping is done calculating. I have found that this bug consistently happens on certain stores but not other stores. It's possible that this is an undocumented Shopify store configuration or simply a frontend bug.

To provide extra information, I know that there shouldn't be any shipping misconfiguration in the store settings because after the shipping calculation comes back, there is no issue. It's only while the shipping is loading that the error message appears.

Has anyone else seen this behavior before?