If a user navigates to a UV link directly, without the service worker
registered, Cyclone's bare server will take over and interpret the URL
as http://go/..., which you definitely didn't want, unless you happen
to work at Google :P
The block inside `if (proxy == 'uv' || 'osana')` is always going to run,
because 'osana' is a truthy value. I hope those aren't bad habits from
Python.