By enabling this options, the moderation bot will automatically moderate duplicate messages. That means if a user send the same message twice within X seconds, the second message will be deleted.
To enable this feature, first you have to create a client on your provider side (check the related documentation for enabling OpenID Connect).Then go to the [plugin settings](/peertube-plugin-livechat/documentation/admin/settings), and enable "{{% livechat_label external_auth_custom_oidc_label %}}".
Note: if you want to restrict allowed redirection urls on the provider side (best security practice), the plugin will show you the url to allow.Just copy it in your OpenID Connect application configuration.