Show featured image in rss-blogrolls

Hello,i want my featured image to appear on other websites blogrolls etc,for example on blogger. I cant find a solution for that,any ideas?

Btw i already know that the code at the end of the post,will add the featured image in your rss feed,but this doesnt fix my problem.

In the items of a blogroll im getting only this tag [image: ‘name’]. No items for thumbnail,only for title and content.

function featuredtoRSS($content) {
global $post;
if ( has_post_thumbnail( $post->ID ) ){
$content = ” . get_the_post_thumbnail( $post->ID, ‘thumbnail’, array( ‘style’ => ‘float:left; margin:0 15px 15px 0;’ ) ) . ” . $content;
}
return $content;
}

add_filter(‘the_excerpt_rss’, ‘featuredtoRSS’);
add_filter(‘the_content_feed’, ‘featuredtoRSS’);