Your Windows 7 platform is no longer supported and that is why you have been moved to the 115 ESR update channel (mozilla-win-eol-esr115). You may have a problem with the cookies with the website problems you describe. I notice DuckDuckGo Privacy Essentials in your extension lists.

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

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You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.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

• https://support.mozilla.org/en-US/kb/clear-cookies-and-site-data-firefox
• https://support.mozilla.org/en-US/kb/how-clear-firefox-cache

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 if userChrome.css/userContent.css is causing the problem.

• switch to the Default System 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

None of these ideas helped.

Couldn't get a screenshot, so here is the verbiage.

Shopify

1)Your connections needs to be verified before you can proceed.

               _______ Verify you are human   Cloudflare

2)Please stand by, while we are checking your browser...

repeats 1 and 2 in an endless loop

There is also a red line through the lock icon.

At scrapbook.com - it goes through the steps, but everything checks out

At rangerink.com and simonsaysstamp.com , it is endless loop time .

Query as to why shopify is even acting as a gatekeeper to these sites?

Does it still happen in a new profile or after refreshing your existing profile?

See:

• https://developers.cloudflare.com/firewall/cf-firewall-rules/cloudflare-challenges/

Cloudflare uses a cookie based challenge and sends a form to the server via GET data appended to the URL. The website creates a cf_clearance cookie when the challenge is resolved and the check finishes properly. If this challenge page keeps reloading then this means that the script isn't working properly and is not able to create this cf_clearance cookie. This can happen if you block cookies or have an extension that blocks cookies.