Nginx 502 Bad Gateway error ONLY in Firefox

Question

I am running a website locally, all the traffic is routed through NGinx which then dispatches requests to PHP pages to Apache and serves static files. Works perfectly in Chrome

Answer 1

I seem to have found a work around that fixed my problem. After some additional Google research, I added the following lines to my Nginx config:

proxy_buffers 8 16k;
proxy_buffer_size 32k;

However, I still don't know why this worked and why only Firefox seemed to have problems. If anyone can shed light on this, or offer a better solution, it would be much appreciated!