While Ross's suggestion lets you load pages that would otherwise fail on nonsense "Referer" header values (which should probably also be classed as a bug in such pages), it does not help you test what happens when no header is sent at all.
While Ross's suggestion lets you load pages that would otherwise fail on nonsense "Referer" header values (which should probably also be classed as a bug in such pages), it does not help you test what happens when no header is sent at all.