Do you mean you want to turn off the chat function in Teams webniar?
As an admin, you can manage the features attendees use for interaction during webinars:
- Chat: You can set chat to be on for everyone, off for everyone, or on for everyone but anonymous users. When chat is set to On for everyone, all meeting and webinar participants can read and write chat messages; the organizer's Meeting chat settings control the chat experience.
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