Ticket #25416: 25416.diff

src/wp-admin/includes/post.php

@@ -1363 +1363 @@
                 // If the new autosave has the same content as the post, delete the autosave.
                 $post = get_post( $post_id );
                 $autosave_is_different = false;
-                foreach ( array_keys( _wp_post_revision_fields() ) as $field ) {
+                foreach ( array_intersect( array_keys( $new_autosave ), array_keys( _wp_post_revision_fields() ) ) as $field ) {
                         if ( normalize_whitespace( $new_autosave[ $field ] ) != normalize_whitespace( $post->$field ) ) {
                                 $autosave_is_different = true;
                                 break;