Today I discovered that in the Knowledge Base we suggest to have two Yubikeys so that if you loose one of them, you can continue to use the other. But Passpack didn’t support more than one Yubikey. Oops… So, today, I decided to fix the issue adding the support for a second Yubikey.
I also modified the process of removing a second factor if you have only one Yubikey and you loose it. In fact, I added the ID of the Yubikey to the Second Factor configuration page. This will be required to unlock your account if necessary. So, please, save it in your records.