* The `asn` field has been removed from the provider model. Please replicate any provider ASN assignments to the ASN model introduced in NetBox v3.1 prior to upgrading.
* The `noc_contact`, `admin_contact`, and `portal_url` fields have been removed from the provider model. Please replicate any data remaining in these fields to the contact model introduced in NetBox v3.1 prior to upgrading.
A new `PluginMenu` class has been introduced, which enables a plugin to inject a top-level menu in NetBox's navigation menu. This menu can have one or more groups of menu items, just like core items. Backward compatibility with the existing `menu_items` has been maintained.