Stop the proxy username/password fields from autocompleting in browsers
In the interface settings screen for an External DHCP or Static NIC there is a username and password for the case that you have an upstream proxy. This always auto-completes with my system username and password which I have allowed my browser to remember. If I had a proxy, it would have a completely different user/pass. As I don't have an upstream proxy I certainly do not want to put anything in these fields.