Hello!
In some browsers I get a Mixed Content error because there's a call for style.css file and that file will be supposedly loading via HTTP protocol and that's what some browsers try to prevent. It's this line that triggers the error. And on line 46 in a source code of main page you see this

I assume that something within a template attempts to load that insecure CSS file (which I'm not even sure that exists in my Joomla tree). I don't know where to find the source of this call and how to stop it. POSSIBLY it's in templates/jp-x2/layouts/template.config.php file on line 103 there's this:
So MAYBE it's the source of the trouble (or maybe not!)

Create an empty css/custom.css and the issue will be done.

OK, thank you! The issue is solved. You can close this thread now...