Do you mean that this website only works via the http:// protocol and that Firefox wants to use the https:// protocol ?

Are you possibly using Private Browsing mode as that has HTTPS first enabled ?

• about:config => dom.security.https_first_pbm = false (default is true)

I am not sure how to answer the first question. In Chrome the the URL does not show http or https in the URL. In about about:config the setting is the default (true). I am not sure if this next is relevant: I had previously set Custom under Privacy and Security, because I had a problem with a different website not loading as it was deemed Insecure. I have just reset to the Standard Setting in Privacy and Security and the problem does not occur with the different website but it still persists with the website problem I encountered today.

As far as I can see I am not using Private Browsing. All mt History is retained. I am sorry if that does not help. I am a bit confused with all this as I am not a tech wizard...

Can you post a link to a publicly accessible page (i.e. no authentication or signing on required)?

Hello cor-el, https://www.signalshares.com/help-centre/

No problems here with accessing that website.

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block content (Adblock Plus, NoScript, DuckDuckGo PE, Disconnect, Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block content.

• make sure your extensions and filters are updated to the latest version
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Firefox shows a purple shield instead of a gray shield at the left end of the location/address bar in case Enhanced Tracking Protection is blocking content. You can click shield icon for more detail and possibly disable the protection. You can check the Web Console for relevant-looking messages about blocked content.

• https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop
• https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection
• https://support.mozilla.org/en-US/kb/trackers-and-scripts-firefox-blocks-enhanced-track

You can try these steps in case of issues with webpages:

You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.

• hold down the Shift key and left-click the Reload button
• press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
• press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings).

"Remove the Cookies" for websites that cause problems:

• Settings -> Privacy & Security
  Cookies and Site Data: "Manage Data"

"Clear the Cache":

• Settings -> Privacy & Security
  Cookies and Site Data -> Clear Data -> [X] Cached Web Content -> Clear

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

• switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
• do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window

• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

• https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop
• https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection
• https://support.mozilla.org/en-US/kb/trackers-and-scripts-firefox-blocks-enhanced-track

Many thanks cor-el! The very first extension that I disabled was my Adblocker Ultimate. The website was then loadable :-)! Thanks so much for the effort you put in to help me. :-).

Load the web page. After the page is loaded, click the AdBlock icon. Now select Disable on <website>. After, reload the page.