Ticket #23497: 23497.41.diff

wp-admin/includes/ajax-actions.php

@@ -2130 +2130 @@
         if ( 0 != $single_revision_id ) {
                 $right_revision = get_post( $single_revision_id );
 
+        //make sure the left revision is the most recent
+        //
+
+        if ( $compare_two_mode && strtotime( $right_revision->post_modified_gmt ) < strtotime( $left_revision->post_modified_gmt ) ) {
+                $temp = $left_revision;
+                $left_revision = $right_revision;
+                $right_revision = $temp;
+        }
+
                 $linesadded=0;
                 $linesdeleted=0;