Verisign and other companies sell identity certification services and when a certificate expires, the URL you click to FSDeveloper could be hijacked to a cloned site, which then could record your session, or even place new software into your computer. This would only happen if you clicked from a webpage or linked message you had not followed before, links before the certificate expired remain valid and the numerical code for the website, the IP address, can't be hijacked.
In large part, the message is more of an incentive to webmasters to renew to avoid embarrassment, as the type of breach these certificates prevent affect random browsers, a type of web traffic this site does not target.
I know about this because I have been using a small, local, less-than-highly-profitable ISP for years and I put up with his 1980's style, ASCII based threat prevention that blocks virtually all gmail addresses, for the simple fact that my email address is my initials. When I converse with my attorney I have to use Yahoo. What gets me is that every web browser is complicit in this extortion, in that I can not permanently flag saw.net as safe. It is my browser, my email and the likelihood of being redirected to a para-site from checking messages is virtually nil.
If you are reading this message: your session has been declared secure by =rk= certification services, Roby