Docker Container question

I am trying to create a Docker container and deploy it on a web server running NGINX but whatever I do, I am just getting Please Wait and Connecting on my app when trying to reach it from http://public_ip_address/, the same notification I get when I am trying to reach from my office PC, so I guess it is some kind of protection not allowing me to view CORS content. I have tried both with Chrome and Firefox and with both I was not able to see it. I don’t know if this is due to some extension I am having or some security restriction.

Any idea how to circumvent this protection? And what exactly is the problem?