Sometimes you may notice that clicking on “Submit” button doesn’t work because Google puts a “Captcha” in the Google Form, for example:
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If you notice this recaptcha, change your form settings and switch off “Response Receipts”.
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Now when you visit Extended Forms, your form will work just fine.
Question: But I want to send Response receipts to the respondents.
Answer: We are working on a feature where Extended Forms will send the receipts to users on the form submit. This feature will soon be announced. Keep yourself updated here.