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JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.

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    prototype.forms.js:435 not responding error on desktop. Unable to enter text on mobile

    Asked by Avertical on October 22, 2015 at 06:16 PM



    The form linked here is giving us issues on mobile devices (both Chrome on Android and Safari on iOS). When someone attempts to fill a text field, the browser does not display the text entered until the user clicks outside the field. Additionally, when I debug the page in my desktop browser, it shows that the prototype.forms.js is not responding. Please let me know what I would be able to do to resolve this issue.

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    JotForm Support Manager

    Answered by Jeanette on October 23, 2015 at 12:27 AM

    I was able to replicate the problem. I guess this is the line you get in the error





    So, let me inform this to our L2 team to have this fixed for you.

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    JotForm Support

    Answered by liyam on October 28, 2015 at 12:25 AM


    The problem with the form is that you have set your autofill with an interval too short that it auto-saves your form every 4 seconds. You might want to change it to every 30 seconds. To change this, you will need to edit your form then do the folllowing steps:

    1. Click Preferences.
    2. Click on Advanced Settings
    3. Edit Auto Fill Settings
    4. Change the values on Auto Save 

    Note: once completed, you will have to clear the cookies of your browser for your browser to get fresh new settings for this.

    If you have other questions or concerns, please do let us know.

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    Answered by Avertical on October 28, 2015 at 10:32 AM



    I tried updating the auto-save interval to 30s, but it seems that the from is still unresponsive on mobile devices. When trying to debug the script in Firefox, it seems that line 252 is hanging: 


    Please let me know if there is anything else I can do with my form to make it work.

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    JotForm Support

    Answered by ashwin_d on October 28, 2015 at 12:41 PM

    Hello Avertical,

    I did check your form and even though you have set the "Auto Fill" to 30 seconds but I am able to replicate the issue you are having. My browser freezes and had to close it down. 

    Let me report it again to our back end team if they are able to figure out the issue. I will also take a look at it later.

    Thank you!

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    JotForm Support

    Answered by liyam on October 29, 2015 at 02:05 PM


    While we're checking on this issue, please disable for the meantime your conditions. We'll keep you posted as soon as we have updates on this matter.

    Thanks for your understanding and we apologize for this inconvenience.