Firefox definitely autofills ports based on your history. Below is a screenshot of it doing it for me. https://imgur.com/a/VRXsyUf https://imgur.com/a/VRXsyUf

Firefox definitely autofills ports based on your history. Below is a screenshot of it doing it for me. https://imgur.com/a/VRXsyUf https://imgur.com/a/VRXsyUf I don't know what is going on with your nginx setup. Most likely you've configured it differently than you think you have, or are making different requests in Firefox and Chome without realizing it. Both firefox and chrome behave the same for me when I make an http request to to a server using https (e.g. http://www.example.com:443/ http://www.example.com:443/)