#1800::Undefined array key "languageStrings"

vtlib/Vtiger/Deprecated.php

@@ -622,6 +622,6 @@ class Vtiger_Deprecated {
 	static function return_app_list_strings_language($language, $module='Vtiger') {
 		require_once 'includes/runtime/LanguageHandler.php';
 		$strings = Vtiger_Language_Handler::getModuleStringsFromFile($language, $module);
-		return $strings['languageStrings'];
+		return isset($strings['languageStrings']) ? $strings['languageStrings'] : [];
 	}
 }
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