Fatal error: Uncaught TypeError: ftp_nlist(): Argument #1 ($ftp) must be of type FTP\Connection, null given in /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php:438 Stack trace: #0 /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php(438): ftp_nlist(NULL, '/var/www/html/w...') #1 /var/www/html/wp-admin/includes/class-wp-filesystem-base.php(231): WP_Filesystem_FTPext->exists('/var/www/html/w...') #2 /var/www/html/wp-admin/includes/class-wp-filesystem-base.php(79): WP_Filesystem_Base->find_folder('/var/www/html/w...') #3 /var/www/html/wp-content/plugins/visualizer/classes/Visualizer/Module.php(536): WP_Filesystem_Base->wp_content_dir() #4 /var/www/html/wp-content/plugins/visualizer/classes/Visualizer/Module/Frontend.php(274): Visualizer_Module->get_user_customization_js() #5 /var/www/html/wp-includes/class-wp-hook.php(324): Visualizer_Module_Frontend->enqueueScripts('') #6 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #7 /var/www/html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #8 /var/www/html/wp-includes/script-loader.php(2265): do_action('wp_enqueue_scri...') #9 /var/www/html/wp-includes/class-wp-hook.php(324): wp_enqueue_scripts('') #10 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #11 /var/www/html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #12 /var/www/html/wp-includes/general-template.php(3050): do_action('wp_head') #13 /var/www/html/wp-includes/template-canvas.php(17): wp_head() #14 /var/www/html/wp-includes/template-loader.php(106): include('/var/www/html/w...') #15 /var/www/html/wp-blog-header.php(19): require_once('/var/www/html/w...') #16 /var/www/html/index.php(17): require('/var/www/html/w...') #17 {main} thrown in /var/www/html/wp-admin/includes/class-wp-filesystem-ftpext.php on line 438