Add the featured image to output of Download Details widget

widgets/download-details-featured-image.php

@@ -0,0 +1,18 @@
+<?php
+/**
+ * Add the featured image to output of Download Details widget
+ */
+
+function sd_edd_download_details_widget_thumbnail( $instance ) {
+
+	// get the ID of the current post
+	$post_id = get_the_ID();
+
+	// grab featured image of the appropriate download
+	if ( 'current' == $instance['download_id'] ) {
+		echo get_the_post_thumbnail( $post_id );
+	} else {
+		echo get_the_post_thumbnail( $instance['download_id'] );
+	}
+}
+add_action( 'edd_product_details_widget_before_purchase_button', 'sd_edd_download_details_widget_thumbnail' );