Fatal error: Uncaught TypeError: WP_Translation_Controller::set_locale(): Argument #1 ($locale) must be of type string, null given, called in /var/www/html/wp-includes/l10n.php on line 799 and defined in /var/www/html/wp-includes/l10n/class-wp-translation-controller.php:87 Stack trace: #0 /var/www/html/wp-includes/l10n.php(799): WP_Translation_Controller->set_locale() #1 /var/www/html/wp-content/plugins/polylang/include/olt-manager.php(106): load_textdomain() #2 /var/www/html/wp-includes/class-wp-hook.php(326): PLL_OLT_Manager->load_textdomains() #3 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #4 /var/www/html/wp-includes/plugin.php(517): WP_Hook->do_action() #5 /var/www/html/wp-content/plugins/polylang/frontend/choose-lang.php(112): do_action() #6 /var/www/html/wp-content/plugins/polylang/frontend/choose-lang-url.php(82): PLL_Choose_Lang->set_language() #7 /var/www/html/wp-content/plugins/polylang/frontend/choose-lang-url.php(34): PLL_Choose_Lang_Url->set_language_from_url() #8 /var/www/html/wp-content/plugins/polylang/frontend/frontend.php(118): PLL_Choose_Lang_Url->init() #9 /var/www/html/wp-content/plugins/polylang/include/class-polylang.php(263): PLL_Frontend->init() #10 /var/www/html/wp-includes/class-wp-hook.php(324): Polylang->init() #11 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #12 /var/www/html/wp-includes/plugin.php(517): WP_Hook->do_action() #13 /var/www/html/wp-settings.php(550): do_action() #14 /var/www/html/wp-config.php(96): require_once('...') #15 /var/www/html/wp-load.php(50): require_once('...') #16 /var/www/html/wp-blog-header.php(13): require_once('...') #17 /var/www/html/index.php(17): require('...') #18 {main} thrown in /var/www/html/wp-includes/l10n/class-wp-translation-controller.php on line 87

Fatal error: Uncaught TypeError: WP_Translation_Controller::set_locale(): Argument #1 ($locale) must be of type string, null given, called in /var/www/html/wp-includes/l10n.php on line 799 and defined in /var/www/html/wp-includes/l10n/class-wp-translation-controller.php:87 Stack trace: #0 /var/www/html/wp-includes/l10n.php(799): WP_Translation_Controller->set_locale() #1 /var/www/html/wp-includes/l10n.php(953): load_textdomain() #2 /var/www/html/wp-includes/class-wp-fatal-error-handler.php(49): load_default_textdomain() #3 [internal function]: WP_Fatal_Error_Handler->handle() #4 {main} thrown in /var/www/html/wp-includes/l10n/class-wp-translation-controller.php on line 87