In such case, try changing the "{{% livechat_label prosody_peertube_uri_label %}}" settings, by setting `http://127.0.0.1:9000` (assuming 9000 is the port on which Peertube listen, ask your instance administrators if you don't know).
If everything is fine in the diagnostic tools, but chat windows remains empty: it can be a Websocket issue.Since Peertube version 5.0.0, there are some additional configuration to do on the server side.Check with the instance administrators that they did not forgot to apply changes listed in the [Peertube v5.0.0 release notes](https://github.com/Chocobozzz/PeerTube/blob/master/CHANGELOG.md#v500).
If you can't fix this immediatly, you can disable Websocket by unchecking "{{% livechat_label disable_websocket_label %}}" in the plugin setting page.In such case, you should also check "{{% livechat_label federation_dont_publish_remotely_label %}}", as chat federation won't work without Websocket.
