Improvement of the error message
This is feedback from some of my donors.
When card details entered but postcode is missed, the popup comes as "postcode missing". But due to the nature of civi form layout some people may already have entered postcode 2 times at this stage, depending on whether billing address is turned off or not from stripe.
The issue seems to be, the popup shows postcode missing but the donor just cant spot where the missing field is! Because its not highlighted or indicated on the form itself. Specially when used credit card autofill from browser.
So, my suggestion is to improve on how the error field is shown after the popup, perhaps to make it obvious by different color or highlighting it. I am sure some of us has experienced if not many...