Whom is the host of your services? I think that comes from your host services and the browser uses what it's given. Check with your hosts services about the http switching.

You can change a setting for your Firefox; of course, this will not change how the site operates.

Unfortunately, the setting is global, not site-specific, so you won't get the benefit of the change on other sites. Here's how:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(2) In the search box in the page, type or paste upgrade_display_content and pause while the list is filtered. Firefox should display multiple preferences.

(3) To toggle a preference from true to false, double-click it. You might only need to change security.mixed_content.upgrade_display_content.image and continue to require a secure connection for audio and video.