Codes utiles

add_filter( 'post_thumbnail_html', 'ravs_hide_featured_image_on_post', 10, 5 );
function ravs_hide_featured_image_on_post( $html, $post_id, $post_thumbnail_id, $size, $attr ){

    if( is_single() )
        $html =''; // hide featured image in post
    return $html;

}

#button {
    border: none;
}