Creating an external VLAN interface does not show the Upstream Proxy, Bandwidth and PPPoE settings
If you create a VLAN interface and set the role to External, additional boxes should appear allowing you to set the Upstream Proxy and Bandwidth parameters, and if the Connection Type is set to PPPoE, it should also show the PPPoE panel containing the Username, Password and MTU.
IIRC, this is the reverse of Todd's initial commit where the extra boxes always showed whether the interface was internal or external. It is like an ajax call has been removed entirely, where it should have just been removed for internal interfaces (or added for external interfaces)