I've created a simple Code Snippet (with run everywhere) to test the upgrader_process_complete hook. I cannot get it to trigger on plugin updates or plugin activation. I see no errors with wp_debug true. function my_custom_upgrader_process_complete($upgrader_object, $options) { error_log('upgrader_process_complete triggered!'); } add_action('upgrader_process_complete', 'my_custom_upgrader_process_complete', 999, 2); I'm using a very basic Wordpress installation with only Code Snippets and Elementor plugin with the Hello theme. Any ideas on troubleshooting? I also tried it with child theme in functions.php.