Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "wp_initialize_theme_preview_hooks" not found or invalid function name in /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/class-wp-hook.php:324 Stack trace: #0 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #1 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/plugin.php(517): WP_Hook->do_action() #2 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-settings.php(486): do_action() #3 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-config.php(78): require_once('/var/www/vhosts...') #4 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-load.php(50): require_once('/var/www/vhosts...') #5 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-blog-header.php(13): require_once('/var/www/vhosts...') #6 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/index.php(17): require('/var/www/vhosts...') #7 {main} thrown in /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/class-wp-hook.php on line 324 Fatal error: Uncaught Error: Class "WP_Translation_Controller" not found in /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/l10n.php:800 Stack trace: #0 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/l10n.php(957): load_textdomain() #1 /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/class-wp-fatal-error-handler.php(49): load_default_textdomain() #2 [internal function]: WP_Fatal_Error_Handler->handle() #3 {main} thrown in /var/www/vhosts/nbries.nl/webspace/httpdocs/nbries.nl/wp-includes/l10n.php on line 800