[403] CSRF verification failed

Good morning,

Unfortunately I get the following error when trying to amend (add new comment) to one of my bitbucket issues:

{{{
Forbidden (403)

CSRF verification failed. Request aborted.

You are seeing this message because this HTTPS site requires a 'Referer header' to be sent by your Web browser, but none was sent. This header is required for security reasons, to ensure that your browser is not being hijacked by third parties.

If you have configured your browser to disable 'Referer' headers, please re-enable them, at least for this site, or for HTTPS connections, or for 'same-origin' requests.

More information is available with DEBUG=True.
}}}

I'm running Windows 7 SP1 x64 with Opera 11.50 (Build 1074).

Attached is a screenshot of my settings. I have also tried adding bitbucket as a security exception and trying form submission without a proxy.

Please fix this ASAP (or if it's a problem on my end, tell me how to fix it).

Thanks,

Samuel Marks