Fatal error: Uncaught Error: Class 'yii\debug\Panel' not found in /opt/lampp/htdocs/io.core.websocket/vendor/yiisoft/yii2-httpclient/src/debug/HttpClientPanel.php:27 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/io.core.websocket/vendor/yiisoft/yii2-httpclient/src/debug/HttpClientPanel.php on line 27