The Peertube instance can configure external authentication providers (Mastodon accounts, Google accounts, ...).In such case, you will see a "{{% livechat_label login_using_external_account %}}" button, that will open a dialog modal.In this dialog modal, there will be some buttons to connect using a remote account.
The plugin has many advanced features.As it is using the [XMPP](https://xmpp.org/) standard "under the hood", it is possible for Peertube administrators to allow advanced usages (connection using XMPP clients, chatbots, bridge to other chat protocols, ...).More information in the relevant sections of this documentation.