Nextcloud Talk is an application that provides chat, audio and visual conferencing through your local devices. It is flexible, allowing you to teleconference with registered users as well as with invited, unregistered guests. Learn how to teleconference with anyone, using Nextcloud Talk.
This tutorial explain how to create a video conference with Nextcloud talk. You can invite people who does not have any nextcloud account.
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https://www.knthost.com/nextcloud/teleconference-using-nextcloud-talk