Add Image node to Wordpress RSS-Feed

to add image into your Wordpress RSS-Feed,

paste this code snippet in your theme functions.php file

add_action('rss2_item', function(){

global $post;

 if(has_post_thumbnail($post->ID)){

  $output = '';

  $thumbnail_ID = get_post_thumbnail_id( $post->ID );

  $thumbnail = wp_get_attachment_image_src($thumbnail_ID, 'thumbnail');

  $output .= '<featuredimage>';

  $output .= $thumbnail[0];

  $output .= '</featuredimage>';



  echo $output;

 }

});