Are you running a developer version of Chrome? For better or worse, starting in July Chrome 68 will begin flagging all http: sites as insecure as part of Google's push for end-to-end web encryption:

https://techcrunch.com/2018/02/08/ch...as-not-secure/

There's a lot of web politics for and against this, but the end result is going to be a lot of web brokenness for a while as sites like this slowly get around to fixing all their issues--like the one you just found.