This is a complementary fix related to pull request 717. If the provided URL also happens to be nil, TTURLRequestQueue::createNSURLRequest will simply crash. This fix makes it a little more robust, and avoids attempting to request a blank URL.
do not attempt to start connection when URL is nil
Facebook has not maintained or supported Three20 for some time, and we are closing its old and outstanding pull requests.
Many, many thanks for your support of the project. If you have any further questions, please don't hesitate to let me know.