That’s not the error the OP is talking about.
Newer versions of Firefox and Chrome bitch because we have a login box on the page and we don’t use https. In the nearly two decades that the SDMB has been around it’s never been a problem, but newer browsers are pushing for better security.
It’s not that big of a deal.
On Firefox, you can disable it by going into about:config (you’ll have to google the exact setting, I don’t remember it off the top of my head), but that enables or disables it everywhere. I don’t think it is possible to enable/disable it on a site by site basis in Firefox.