Merge pull request #995 from pupi1985/patch-169

Another PHP 8 fix

Author: svivian

qa-include/app/format.php

@@ -165,7 +165,7 @@ function qa_get_favorite_non_qs_map()
 						break;
 
 					case QA_ENTITY_TAG:
-						$qa_favorite_non_qs_map['tag'][qa_strtolower($favorite['tags'])] = true;
+						$qa_favorite_non_qs_map['tag'][qa_strtolower($favorite['tags'] ?? '')] = true;
 						break;
 
 					case QA_ENTITY_CATEGORY: