Wordpress 5.0: The editor encountered an unexpected error. When edit a draft or create a new post. Solved.

Warning: Uninitialized string offset 0 in /usr/local/www/ppblog/wp-content/themes/ppblog/library/w3c.php on line 17 Wordpress 5.0: The editor encountered an unexpected error. When edit a draft or create a new post. Solved. - PushPanel.io Fatal error: Uncaught ValueError: Unknown format specifier """ in /usr/local/www/ppblog/wp-content/plugins/shortcodes-ultimate/inc/core/assets.php:126 Stack trace: #0 /usr/local/www/ppblog/wp-content/plugins/shortcodes-ultimate/inc/core/assets.php(126): sprintf('%1$s.