PHP Deprecated Warning – [yii\base\ErrorException](https://www.yiiframework.com/doc-2.0/yii-base-errorexception.html)
Using null as an array offset is deprecated, use an empty string instead
1. in /var/www/html/vendor/yiisoft/yii2-debug/src/controllers/DefaultController.phpat line 111
102103104105106107108109110111112113114115116117118119120     * @throws NotFoundHttpException if debug data not found.
     */
    public function actionView($tag = null, $panel = null)
    {
        if ($tag === null) {
            $tags = array_keys($this->getManifest());
            $tag = reset($tags);
        }
        $this->loadData($tag);
        if (isset($this->module->panels[$panel])) {
            $activePanel = $this->module->panels[$panel];
        } else {
            $activePanel = $this->module->panels[$this->module->defaultPanel];
        }
 
        if ($activePanel->hasError()) {
            Yii::$app->errorHandler->handleException($activePanel->getError());
        }
 
2. in /var/www/html/vendor/yiisoft/yii2-debug/src/controllers/DefaultController.php at line 111– [yii\base\ErrorHandler::handleError](https://www.yiiframework.com/doc-2.0/yii-base-errorhandler.html#handleError()-detail)()