I'd suggest those watching on the match streaming service get familiar with the 'How can I watch or listen to games?' in the FAQ via the County TV link on the website.

If in the past you have used a web browser on a smart TV to login, it seems you can't anymore and you will need now to cast to your smart TV or connect your Phone/PC or Tablet via an HDMI lead.
The FAQ talks about the 'official County app' but I have no clue as to what that is. I assume it refers to the County TV link.

I have asked the club for clarification and will post any reply should I get one.