Neos\Flow\Session\TransientSession::removeTag PHP Method

    public function removeTag($tag)
    {
        if ($this->started !== true) {
            throw new Exception\SessionNotStartedException('The session has not been started yet.', 1422551049);
        }
        if (isset($this->tags[$tag])) {
            unset($this->tags[$tag]);
        }
    }