Fatal error: Uncaught TypeError: ucfirst(): Argument #1 ($string) must be of type string, null given in /opt/ojs/lib/pkp/classes/i18n/LocaleMetadata.php:190 Stack trace: #0 /opt/ojs/lib/pkp/classes/i18n/LocaleMetadata.php(190): ucfirst() #1 /opt/ojs/plugins/generic/defaultTranslation/DefaultTranslationPlugin.php(123): PKP\i18n\LocaleMetadata->getScript() #2 [internal function]: APP\plugins\generic\defaultTranslation\DefaultTranslationPlugin->APP\plugins\generic\defaultTranslation\{closure}() #3 /opt/ojs/plugins/generic/defaultTranslation/DefaultTranslationPlugin.php(120): uasort() #4 /opt/ojs/plugins/generic/defaultTranslation/DefaultTranslationPlugin.php(89): APP\plugins\generic\defaultTranslation\DefaultTranslationPlugin->getSuitableLocales() #5 /opt/ojs/plugins/generic/defaultTranslation/DefaultTranslationPlugin.php(54): APP\plugins\generic\defaultTranslation\DefaultTranslationPlugin->translate() #6 [internal function]: APP\plugins\generic\defaultTranslation\DefaultTranslationPlugin->APP\plugins\generic\defaultTranslation\{closure}() #7 /opt/ojs/lib/pkp/classes/plugins/Hook.php(139): call_user_func_array() #8 /opt/ojs/lib/pkp/classes/plugins/Hook.php(113): PKP\plugins\Hook::run() #9 /opt/ojs/lib/pkp/classes/i18n/Locale.php(421): PKP\plugins\Hook::call() #10 /opt/ojs/lib/pkp/classes/i18n/Locale.php(104): PKP\i18n\Locale->translate() #11 /opt/ojs/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php(938): PKP\i18n\Locale->get() #12 /opt/ojs/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php(973): trans() #13 /opt/ojs/plugins/themes/healthSciences/HealthSciencesThemePlugin.inc.php(38): __() #14 /opt/ojs/lib/pkp/classes/plugins/ThemePlugin.php(130): HealthSciencesThemePlugin->init() #15 [internal function]: PKP\plugins\ThemePlugin->themeRegistered() #16 /opt/ojs/lib/pkp/classes/plugins/Hook.php(139): call_user_func_array() #17 /opt/ojs/lib/pkp/classes/plugins/Hook.php(113): PKP\plugins\Hook::run() #18 /opt/ojs/lib/pkp/classes/plugins/PluginRegistry.php(128): PKP\plugins\Hook::call() #19 /opt/ojs/lib/pkp/classes/template/PKPTemplateManager.php(1392): PKP\plugins\PluginRegistry::loadCategory() #20 /opt/ojs/lib/pkp/classes/plugins/Plugin.php(403): PKP\template\PKPTemplateManager::getManager() #21 /opt/ojs/lib/pkp/classes/plugins/Plugin.php(137): PKP\plugins\Plugin->_registerTemplateResource() #22 /opt/ojs/lib/pkp/classes/plugins/LazyLoadPlugin.php(34): PKP\plugins\Plugin->register() #23 /opt/ojs/plugins/generic/customBlockManager/CustomBlockManagerPlugin.php(54): PKP\plugins\LazyLoadPlugin->register() #24 /opt/ojs/lib/pkp/classes/plugins/PluginRegistry.php(76): APP\plugins\generic\customBlockManager\CustomBlockManagerPlugin->register() #25 /opt/ojs/lib/pkp/classes/plugins/PluginRegistry.php(121): PKP\plugins\PluginRegistry::register() #26 [internal function]: PKP\plugins\PluginRegistry::PKP\plugins\{closure}() #27 /opt/ojs/lib/pkp/classes/plugins/PluginRegistry.php(121): array_walk_recursive() #28 /opt/ojs/lib/pkp/classes/core/Dispatcher.php(155): PKP\plugins\PluginRegistry::loadCategory() #29 /opt/ojs/lib/pkp/classes/core/PKPApplication.php(388): PKP\core\Dispatcher->dispatch() #30 /opt/ojs/index.php(21): PKP\core\PKPApplication->execute() #31 {main} thrown in /opt/ojs/lib/pkp/classes/i18n/LocaleMetadata.php on line 190