Hi @Roger Roger
Thank you for posting in the community.
I would like to confirm with you first what you are asking, are you worried that when site private settings are set to public, users who visit the site will be added to the group of Microsoft teams.
If I have misunderstood your question, I would appreciate it if you would add relevant pictures or more detailed text descriptions to your question. This will help me understand your question better. In addition, please pay attention that all your private information will be coded. Thank you for your time and efforts in advance.
If I understand correctly, then you don't have to worry about users being automatically added to the group of Microsoft teams.
I tested the question in my side and here is the result:
First, I set the site to public and jinwei (a user) is no in the group of Microsoft teams which is called Karley0606.
Second, jinwei visited this public site, but the user was not added in Karley0606 (the group of Microsoft teams).
You can test this on your site. Feel free to contact to me if you have any concerns.
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