From near the Live Chat heading, click on the “EDIT” button to open Live Stream Settings:
From Stream settings, select Live Chat, and then choose to turn off Enable Live Chat and then click Save:
This will disable live chat for the current Zoom Meeting/Live Stream – however, YouTube does not remember this
setting as a default (nor is there currently a way to force a disabled default state) and therefore every YouTube Live
Stream that you start from Zoom will require you to repeat these steps if you want chat disabled.
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