Add Field Settings option for Dropdown to make an API call [RESOLVED]

I’d like to write a plugin that will add an option to the dropdown field so that I can add a URL to a web API. Something like in the image below.

Then when a form is viewed, I would have the plugin look for the “URL to Web API” field value, fetch the data from the API and populate the dropdown. Like outlined here: https://docs.gravityforms.com/dynamically-populating-drop-down-or-radio-buttons-fields

Is there documentation on how to add the “URL to Web API” field so it is displayed in the Field Settings?

The example in this documentation is the best starting point I’ve been able to find. Should hopefully get you most of the way there.

gform_field_advanced_settings - Gravity Forms Documentation

I think that is what I need. Thanks for pointing it out.