--- wikiplugin_formula.php
@@ -102,7 +102,7 @@
                }
                $file = $tmpf . ".png";
                $html = "<img src=\"temp/" .$file.
-                       "\" alt=\"" .$data. "\" ".
+                       "\" alt=\"~np~" .$data. "~/np~\" ".
                        "align=\"middle\">";
        }
        return $html;