The test returns that HSTS requires “subdomain” and “preload” directives enabled. However, in the plugin settings it sounds like they should be activated only if the site is on https. Mine is, so why I get a “No HSTS header is present” error whereas I had a A+ result before?
Moreover, it degraded from A+ to D and mentions that inclusion in the preload list has permanent consequences and is not easy to undo. So how do I go back to normal now?