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If I am not mistaken we are using prototype, however, I am not sure if we have other JS libraries being used. We also have some widgets that may used other JS framework. You can download your form's full source code, you should be able to see the JS libraries that are loaded through there. Here's a guide on how to get the full source code of the form: https://www.jotform.com/help/104-How-to-get-the-Full-Source-Code-of-your-Form
I hope that helps.