Issue Summary

Configuring the custom field inside the workflow post function should reflect the right message when the field is removed from the UI during the status transition inside the ticket.

Steps to Reproduce

1. Create a custom field and configure the field inside the workflow post function.
2. And then delete the same custom field 
3. Now change the given transition.
4. You will see a popup message "Internal Server Error"

Expected Results

The pop-up needs to be more customised and add relevant messages apart from "Internal Server Error"

Actual Results

"Internal Server Error"

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available