Fatal error: Uncaught Error: Class 'WP_Filesystem_Base' not found in /home/refref/public_html/wp-post-to-pdf-enhanced-cache-20250414195233/wp-post-to-pdf-enhanced-cache/includes/class-wp-filesystem-ftpext.php:16 Stack trace: #0 {main} thrown in /home/refref/public_html/wp-post-to-pdf-enhanced-cache-20250414195233/wp-post-to-pdf-enhanced-cache/includes/class-wp-filesystem-ftpext.php on line 16