Fatal error: Uncaught Error: Call to undefined function add_filter() in /opt/app-root/src/wp-content/plugins/jetpack/modules/theme-tools/content-options/featured-images-fallback.php:136 Stack trace: #0 {main} thrown in /opt/app-root/src/wp-content/plugins/jetpack/modules/theme-tools/content-options/featured-images-fallback.php on line 136