I'm using Vodafone and I'm seeing an "X-VF-ACR" header in my headers that contains a very long base64-encoded string. Anyone any idea what it is? (Edit: Looks

I'm using Vodafone and I'm seeing an "X-VF-ACR" header in my headers that contains a very long base64-encoded string. Anyone any idea what it is? (Edit: Looks like a big bunch of binary)