I have a simple form built in Umbraco Forms with a typical set of fields:

• Name
• Email address
• Message
• reCAPTCHA v3

I'd like to store the form information in the Umbraco back office, but also send the user's email address through to MailChimp.

Per René Pjengaard's suggestion in this forum thread, it seems like I should be able to achieve this using Umbraco Forms' built-in Send Form to URL workflow. I've tried a number of different configurations, and I can't seem to get it to work: the MailChimp workflow always times out.

I've also tried:

• Adding the MailChimp form parameters as hidden form fields and mapping their values, emulating the submission of an embedded MailChimp forms builder form.
• Omitting the MailChimp f_id parameter and using MERGE0 instead of EMAIL, emulating the submission of a standard MailChimp subscribe form.
• Embedding the MailChimp form parameters into the URL and using GET, emulating hitting the URL via web browser.

Questions:

• What am I missing here?
• Is it possible to see exactly what Umbraco is sending to the specified URL?
• Has anyone managed to set this up successfully?