Zoho Connect Widget not populating zoho.loginuserid field

Zoho Connect Widget not populating zoho.loginuserid field

I have a form (created within Zoho Connect) that uses a deluge script to pre-populate the user's email by using the zoho.loginuserid system variable in a Workflow that is triggered by loading of the form. I have also tried triggering the workflow on successful submission. It is a 1-line workflow:
  1. input.Employee_Email = zoho.loginuserid;
The process works great when I'm using the app directly (via Custom Apps -> Form) however, when I embed the app as a widget in the dashboard, the zoho.loginuserid field is always null.

How can I populate the user's email when the app is embedded as a widget?