Nginx Browser Module Troubleshooting

I’m sure I’m missing something simple here but I’m using an Nginx
browser detection routine (copied from browsers.conf · GitHub)
but it doesn’t seem to be working at all. I have tested by changing the
script to make my browser an ancient_browser but it never redirects me
and always lets me into the application. I can confirm that it is
loading this file by putting a syntax error in it and restarting nginx
to see it complain and I’ve checked the nginx logs and nothing of
consequence seems to be logged. How can I further troubleshoot this?

Posted at Nginx Forum: