It's somewhat secondary to the way Groups.io is organized that subgroups have a tendency to "disappear."  But they're still there.

For those who really wish to chat via a list, anyone who is a member of the NVDA group can subscribe to the chat subgroup.  Here are the addresses:

• Post: chat@nvda.groups.io
• Subscribe: chat+subscribe@nvda.groups.io
• Unsubscribe: chat+unsubscribe@nvda.groups.io
• Group Owner: chat+owner@nvda.groups.io
• Help: chat+help@nvda.groups.io

This information needs the occasional bump and repetition, so I'm giving it one:

For those who really wish to chat about any topic not directly NVDA-related with people they know from the NVDA Group via a list, you can subscribe to the chat subgroup.  Here are the addresses:

• Post: chat@nvda.groups.io
• Subscribe: chat+subscribe@nvda.groups.io
• Unsubscribe: chat+unsubscribe@nvda.groups.io
• Group Owner: chat+owner@nvda.groups.io
• Help: chat+help@nvda.groups.io

Since the Chat Group is really just beginning to ramp up, I'd even encourage you to make "See Chat" posts to the main group as the signal flare that you're asking about something there, or sharing information there.   For example, "See Chat: Looking for Advice on TalkBack from those who use it," to let people know who can offer advice that the topic exists and take a look.   It then allows the conversation to be as freewheeling as the participants wish in the Chat subgroup.