diff -r 3d4e9c994f10 -r a86126ab1dd4 wp/wp-includes/class-wp-ajax-response.php
--- a/wp/wp-includes/class-wp-ajax-response.php	Tue Oct 22 16:11:46 2019 +0200
+++ b/wp/wp-includes/class-wp-ajax-response.php	Tue Dec 15 13:49:49 2020 +0100
@@ -18,6 +18,7 @@
 	 * Constructor - Passes args to WP_Ajax_Response::add().
 	 *
 	 * @since 2.1.0
+	 *
 	 * @see WP_Ajax_Response::add()
 	 *
 	 * @param string|array $args Optional. Will be passed to add() method.
@@ -54,7 +55,7 @@
 	 *     @type int|false       $old_id       The previous response ID. Used as the value for the response type
 	 *                                         `old_id` attribute. False hides the attribute. Default false.
 	 *     @type string          $position     Value of the response type `position` attribute. Accepts 1 (bottom),
-	 *                                         -1 (top), html ID (after), or -html ID (before). Default 1 (bottom).
+	 *                                         -1 (top), HTML ID (after), or -HTML ID (before). Default 1 (bottom).
 	 *     @type string|WP_Error $data         The response content/message. Also accepts a WP_Error object if the
 	 *                                         ID does not exist. Default empty.
 	 *     @type array           $supplemental An array of extra strings that will be output within a `<supplemental>`
@@ -73,14 +74,14 @@
 			'supplemental' => array(),
 		);
 
-		$r = wp_parse_args( $args, $defaults );
+		$parsed_args = wp_parse_args( $args, $defaults );
 
-		$position = preg_replace( '/[^a-z0-9:_-]/i', '', $r['position'] );
-		$id       = $r['id'];
-		$what     = $r['what'];
-		$action   = $r['action'];
-		$old_id   = $r['old_id'];
-		$data     = $r['data'];
+		$position = preg_replace( '/[^a-z0-9:_-]/i', '', $parsed_args['position'] );
+		$id       = $parsed_args['id'];
+		$what     = $parsed_args['what'];
+		$action   = $parsed_args['action'];
+		$old_id   = $parsed_args['old_id'];
+		$data     = $parsed_args['data'];
 
 		if ( is_wp_error( $id ) ) {
 			$data = $id;
@@ -90,8 +91,9 @@
 		$response = '';
 		if ( is_wp_error( $data ) ) {
 			foreach ( (array) $data->get_error_codes() as $code ) {
-				$response .= "<wp_error code='$code'><![CDATA[" . $data->get_error_message( $code ) . ']]></wp_error>';
-				if ( ! $error_data = $data->get_error_data( $code ) ) {
+				$response  .= "<wp_error code='$code'><![CDATA[" . $data->get_error_message( $code ) . ']]></wp_error>';
+				$error_data = $data->get_error_data( $code );
+				if ( ! $error_data ) {
 					continue;
 				}
 				$class = '';
@@ -117,8 +119,8 @@
 		}
 
 		$s = '';
-		if ( is_array( $r['supplemental'] ) ) {
-			foreach ( $r['supplemental'] as $k => $v ) {
+		if ( is_array( $parsed_args['supplemental'] ) ) {
+			foreach ( $parsed_args['supplemental'] as $k => $v ) {
 				$s .= "<$k><![CDATA[$v]]></$k>";
 			}
 			$s = "<supplemental>$s</supplemental>";
@@ -128,7 +130,7 @@
 			$action = $_POST['action'];
 		}
 		$x  = '';
-		$x .= "<response action='{$action}_$id'>"; // The action attribute in the xml output is formatted like a nonce action
+		$x .= "<response action='{$action}_$id'>"; // The action attribute in the xml output is formatted like a nonce action.
 		$x .= "<$what id='$id' " . ( false === $old_id ? '' : "old_id='$old_id' " ) . "position='$position'>";
 		$x .= $response;
 		$x .= $s;