You can choose from several different sets the default avatars that will be used for chat users. Please refer to the documentation: <a href="https://livingston.frama.io/peertube-plugin-livechat/documentation/admin/settings/" target="_blank">Settings</a>.
Try to autodetect colors from user's current theme.<br> When this setting is enabled, the plugin tries to auto-detect colors to apply to the chat theme.<br> If this is not correctly working for some of your Peertube theme, you can disable this option. You can report the bug on the official <a href="https://github.com/JohnXLivingston/peertube-plugin-livechat/issues" target="_blank"> issue tracker </a>. Don't forget to specify which theme is not working.