diff --git src/wp-admin/revision.php src/wp-admin/revision.php
index 458a749262..e6561815c4 100644
--- src/wp-admin/revision.php
+++ src/wp-admin/revision.php
@@ -131,7 +131,6 @@ if ( ! empty( $post->post_type ) && 'post' !== $post->post_type ) {
 } else {
 	$parent_file = 'edit.php';
 }
-$submenu_file = $parent_file;
 
 wp_enqueue_script( 'revisions' );
 wp_localize_script( 'revisions', '_wpRevisionsSettings', wp_prepare_revisions_for_js( $post, $revision_id, $from ) );
@@ -164,8 +163,8 @@ require_once ABSPATH . 'wp-admin/admin-header.php';
 ?>
 
 <div class="wrap">
-	<h1 class="long-header"><?php echo $h1; ?></h1>
-	<?php echo $return_to_post; ?>
+	<h1 class="long-header"><?php echo esc_html( $h1 ); ?></h1>
+	<?php echo esc_html( $return_to_post ); ?>
 </div>
 <?php
 wp_print_revision_templates();