In November 2020 the Netlify backend engineer Jen said on this post:
Hey @paweljurczynski,
We usually return a 303 when there is an issue with the reCAPTCHA. Are you using a custom reCAPTCHA? If so, can you confirm that it is configured to work with your domain (you’d do that in your Google dashboard)? If not, can you please share your form code? It could be that you set data-netlify-recaptcha=“true” but then do not create the necessary div with the reCAPTCHA in the body of your form.
Chris McCraw emailed me yesterday with:
303 responses are not common on our platform, so I am 99% sure that none of the code Netlify has written would cause this. We use exclusively 301 and 302 redirects in our automatic redirects and in the code we publish such as the next-runtime, or in responding to a form submission
So I must be in the 1%.
I’ve spent an all-nighter and 18 straight hours trying to fix this issue. Can we work together to investigate why Netlify is rejecting my reCAPTCHA v2 invisible?