diff -r 3d4e9c994f10 -r a86126ab1dd4 wp/wp-admin/includes/class-automatic-upgrader-skin.php
--- a/wp/wp-admin/includes/class-automatic-upgrader-skin.php	Tue Oct 22 16:11:46 2019 +0200
+++ b/wp/wp-admin/includes/class-automatic-upgrader-skin.php	Tue Dec 15 13:49:49 2020 +0100
@@ -30,19 +30,21 @@
 	 *
 	 * @see request_filesystem_credentials()
 	 *
-	 * @param bool   $error                        Optional. Whether the current request has failed to connect.
-	 *                                             Default false.
-	 * @param string $context                      Optional. Full path to the directory that is tested
-	 *                                             for being writable. Default empty.
-	 * @param bool   $allow_relaxed_file_ownership Optional. Whether to allow Group/World writable. Default false.
+	 * @param bool|WP_Error $error                        Optional. Whether the current request has failed to connect,
+	 *                                                    or an error object. Default false.
+	 * @param string        $context                      Optional. Full path to the directory that is tested
+	 *                                                    for being writable. Default empty.
+	 * @param bool          $allow_relaxed_file_ownership Optional. Whether to allow Group/World writable. Default false.
 	 * @return bool True on success, false on failure.
 	 */
 	public function request_filesystem_credentials( $error = false, $context = '', $allow_relaxed_file_ownership = false ) {
 		if ( $context ) {
 			$this->options['context'] = $context;
 		}
-		// TODO: fix up request_filesystem_credentials(), or split it, to allow us to request a no-output version
-		// This will output a credentials form in event of failure, We don't want that, so just hide with a buffer
+		/*
+		 * TODO: Fix up request_filesystem_credentials(), or split it, to allow us to request a no-output version.
+		 * This will output a credentials form in event of failure. We don't want that, so just hide with a buffer.
+		 */
 		ob_start();
 		$result = parent::request_filesystem_credentials( $error, $context, $allow_relaxed_file_ownership );
 		ob_end_clean();
@@ -58,8 +60,9 @@
 
 	/**
 	 * @param string|array|WP_Error $data
+	 * @param mixed                 ...$args Optional text replacements.
 	 */
-	public function feedback( $data ) {
+	public function feedback( $data, ...$args ) {
 		if ( is_wp_error( $data ) ) {
 			$string = $data->get_error_message();
 		} elseif ( is_array( $data ) ) {
@@ -72,8 +75,6 @@
 		}
 
 		if ( strpos( $string, '%' ) !== false ) {
-			$args = func_get_args();
-			$args = array_splice( $args, 1 );
 			if ( ! empty( $args ) ) {
 				$string = vsprintf( $string, $args );
 			}