use Module_Name/template/path format instead of using template/path in Block class to ensure extensibility of the class. not doing so causes invalid template errors after extending the block class via preference

Author: Jakhotiya

app/code/Magento/Review/Block/Product/ReviewRenderer.php

@@ -18,8 +18,8 @@ class ReviewRenderer extends \Magento\Framework\View\Element\Template implements
      * @var array
      */
     protected $_availableTemplates = [
-        self::FULL_VIEW => 'helper/summary.phtml',
-        self::SHORT_VIEW => 'helper/summary_short.phtml',
+        self::FULL_VIEW => 'Magento_Review::helper/summary.phtml',
+        self::SHORT_VIEW => 'Magento_Review::helper/summary_short.phtml',
     ];
 
     /**