My site is a freight forwarding company.
When customers submit an order, we create a custom post "Shipment"
There is a custom field "Shipment Status".
When the status changes e.g. from "Order Received" to "Preparing for Shipping" we want this to trigger an email.
I assume what we want is WHEN TO SEND THIS NOTIFICATION -> WHEN CUSTOM FIELDS ARE MODIFIED
But it has a rather cryptic warning: "You need to add fields to trigger notifications"
What fields? And where?
btw we want the email to go to the Customer Email which is one of the custom fields in the Shipment custom post type.
I've tested this for simple options like "When submitting the form" but that doesnt seem to work.
It's ok. Figured it out on my own.
Seems like you need to enter a condition in the additional field conditions.
Something arbitrary like:
"cargo-status" <> 999
.. and check the box "Only if field value has changed".