    private function clearStackToTableContext($elements) {
        /* When the steps above require the UA to clear the stack back to a
        table context, it means that the UA must, while the current node is not
        a table element or an html element, pop elements from the stack of open
        elements. If this causes any elements to be popped from the stack, then
        this is a parse error. */
        while(true) {
            $node = end($this->stack)->nodeName;

            if(in_array($node, $elements)) {
                break;
            } else {
                array_pop($this->stack);
            }
        }
    }
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.