Fatal error: Uncaught Error: Class "Composer\Installers\BaseInstaller" not found in /home/oxygenco/prod/wordpress/wp-content/plugins/sitepress-multilingual-cms/vendor/composer/installers/src/Composer/Installers/YawikInstaller.php:12 Stack trace: #0 {main} thrown in /home/oxygenco/prod/wordpress/wp-content/plugins/sitepress-multilingual-cms/vendor/composer/installers/src/Composer/Installers/YawikInstaller.php on line 12