Honestly that looks like something specific to your machine/setup. Zorin and Firefox might have a root SSL cert mismatch.
I just did an SSL report on the SSL certificate, and it is perfectly valid, receiving an A minus grade, so it should be working for you. Can you investigate how the SSL certificate looks like for you in Firefox? I’ll be honest, no one else is reporting an issue logging in like this, and it’s also not even specific to the daily briefing.
