stumped on add_action hook to delete_comment – any ideas?

Unless you’re passing $force_delete as true when calling wp_delete_comment(), the delete_comment hook doesn’t fire. This is because WordPress calls wp_trash_comment() at the beginning of wp_delete_comment() if $force_delete isn’t set true.

Try hooking into the trash_comment action hook:

function _dbdb_delete_comment( $comment_id ){
    $filter = current_filter();
    var_dump( $filter );
    var_dump( $comment_id );
    wp_die( __FUNCTION__ );
 }

add_action('delete_comment', '_dbdb_delete_comment' );
add_action('trash_comment', '_dbdb_delete_comment' );

I added that to my theme’s functions file and checked my network response tab in Chrome Dev tools. I tested by deleting (trashing) a comment through the Comments screen in the Admin. It worked as expected.

The filter that was returned was trash_comment.