Apparently firefox (flox, and the rest of the pack) would not allow me to open the site. It says:
This address is restrictedWhat if I understand the risk and I am doing it on purpose (I am redirecting port 21 to a web server as an experiment to by-passing firewall)? Can I bypass this protection?
This address uses a network port which is normally used for purposes other than Web browsing. Firefox has cancelled the request for your protection.
I tried other browsers, and only Safari (on a Mac) allows me to do it. (Don't know whether this is good or bad.) Any comments on this?