public function connection_warning() {
        $options = array('filter' => false, 'newlines' => false);
        $warning = format_text(get_string('connectionerror', 'quiz'), FORMAT_MARKDOWN, $options);
        $ok = format_text(get_string('connectionok', 'quiz'), FORMAT_MARKDOWN, $options);
        return html_writer::tag('div', $warning,
                    array('id' => 'connection-error', 'style' => 'display: none;', 'role' => 'alert')) .
                    html_writer::tag('div', $ok, array('id' => 'connection-ok', 'style' => 'display: none;', 'role' => 'alert'));
    }