Not yet. I just use a different browser for now. It's an intermittent issue where it just randomly fails the SSL handshake.

Secure Connection Failed

An error occurred during a connection to www.sepaq.com. SSL received an unexpected Server Hello handshake message.

Error code: SSL_ERROR_RX_UNEXPECTED_SERVER_HELLO

Apparently I can also try to change SSL and TLS options. I'll experiment a bit and see. I guess I should also let the website know. Maybe it's just a configuration issue on their end, and other Firefox users are facing the same error. I use this website to make camping reservations and as winter is coming where I am, I have a few months to try different options before it becomes a bit more annoying again.