Hi @bcoplin,
Thank you very much for your report. This seems to be a bug on one of the plugin Javascript files. I reported this on the issue tracker.
Please kindly stay tuned for the upcoming plugin release to have a fix which you can follow up on our Changelog.
As there is no ETA for the bug fixes and if you urgently need the form I suggest that you use the method below:
You can also, create/generate a form on MailChimp and integrate that to your site, using the Content Area element for adding the code.
Add a Signup Form to Your Website
Thanks.