Fatal error: Uncaught Error: Call to undefined function add_shortcode() in /home/kacperg/public_html/kacpergr/wp-content/plugins/jetpack/modules/shortcodes/twitter-timeline.php:66 Stack trace: #0 {main} thrown in /home/kacperg/public_html/kacpergr/wp-content/plugins/jetpack/modules/shortcodes/twitter-timeline.php on line 66