Index: src/wp-admin/includes/file.php
===================================================================
--- src/wp-admin/includes/file.php	(revisione 40289)
+++ src/wp-admin/includes/file.php	(copia locale)
@@ -500,8 +500,9 @@
 	if ( ! $tmpfname )
 		return new WP_Error('http_no_file', __('Could not create Temporary file.'));
 
-	$response = wp_safe_remote_get( $url, array( 'timeout' => $timeout, 'stream' => true, 'filename' => $tmpfname ) );
+	$args = apply_filters( 'download_url_args', array( 'timeout' => $timeout, 'stream' => true, 'filename' => $tmpfname ) );
 
+	$response = wp_safe_remote_get( $url, $args);
 	if ( is_wp_error( $response ) ) {
 		unlink( $tmpfname );
 		return $response;