Google Invisible reCaptcha: Duplicate submission using reCAPTCHA

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    Asked on December 27, 2017 at 06:16 PM

    It seems that there may be a problem with the Google Invisible reCAPTCHA widget as it sometimes (more often than not) will make a duplicate submission at exactly the same time with the same data except the for the reCAPTCHA field which will be either empty or with the value "Verified".

    Can you confirm this or do you know how to avoid it?


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    Answered on December 27, 2017 at 07:18 PM

    I wasn't able to reproduce the duplicate submission issue but it prompts with a different issue when using the Google Invisible reCaptcha widget.


    Can you please confirm if you are still able to reproduce the duplicate submissions problem and also the issue with the Captcha window size (I'll create a separate report for the sizing issue)? 

    Update: Sorry, I found the width settings for the google invisible recaptcha widget. Please disregard that part.


    Looking forward for your response.

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    Answered on January 03, 2018 at 05:27 PM

    Sorry for the late update.

    Yes, I have been able to recreate the problem, but not every time.

    I've just been able to do it using a chrome browser (not sure if it could be a browser issue).


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    Answered on January 03, 2018 at 07:18 PM

    Can you please share the form URL or ID so we can check and further investigate. 

    Looking forward for your response.

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    Answered on January 04, 2018 at 05:12 AM

    As I can see in your Thank you page you have a .php file that retrieves the data. That might be the issue why you are getting a duplicate submission. 

    Can you Turn on the unique submission, to prevent duplicate submissions. Please follow the instructions on the link below on how to do that:

    Let us know if you have any other question.

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    Answered on January 04, 2018 at 06:11 AM

    I see your test and that went in as a duplicate as well, with 1 second between submits.

    This time though, the recaptcha field was populated with the status "Verified" in both forms.

    I feel I had tried the unique submissions feature, only to receive an error message that it had already been submitted, leaving the user with the error screen instead of the confirmation page.

    I will try it again just to make sure that it was not me that did something wrong.

    Just for clarification, the "Thank You" php page only does retrieves a submission using the posted ID through an API call.

    Actually when posting this answer, I'll get an "Spam check error" if I haven't checked the recaptcha before posting - maybe that is the problem, if the submit behaviour is not blocked but allowed to be posted.

    I think a work around could be to put the recaptcha on page one of the form and do the check there. I'll give both solutions a try.