VM interface creation form not showing custom fields

[gmazoyer]

NetBox version

v2.11.7

Python version

3.7

Steps to Reproduce

1. Add a new custom field to the Virtualization / Interface model
2. Create a new VM
3. Create a new interface on the previously created VM

Expected Behavior

The creation form should display all form fields including custom ones.

Observed Behavior

The creation form displays only built-in field for a VM interface but not the custom ones. When editing a VM interface, the edition form, however, shows the custom fields.