Comment 10 for bug 597324

A test passed using a simple search query, but failed with No REFERRER Header error using the example bug URL (converting to edge). This would be because a form POST needs to be done due to the size of the query string.

Even if the Canonical SSO starts sending the REFERRER headers, that doesn't mean 3rd party OPs will provide it when we want to support them, so ideally we should relax this restriction for the login process.