Only receiving an empty response with 200 status code when using CORS on Nginx 1.14

[krionz]

The problem actually was with my understanding of the CORS policy. When i
make a PATCH the browser makes an OPTIONS to check if i can use the PATCH
method, and even if i answer this OPTIONS request saying that i accept the
PATCH method, when i receive the actual PATCH request i must again answer
this request saying that i allow the PATCH request, otherwise the browser
will not allow me to use the answer given by my server.

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,282474,283775#msg-283775