Take a look at the Spaces list to see the icon next to the new spaces. After you open the space for the first time, the icon goes away.

If you leave a space and get added to it again later, you'll see the icon again.


 

If you don’t see the notification, check that you haven’t turned off notifications for all spaces. See Set Notifications for All Spaces for more details.

You'll see the icon on Webex Teams for iPhone, iPad, and Android, too.