Saying "don't use Firefox" is not a helpful solution.

You can check the connection settings.

• Settings -> General -> Network: Connection -> Settings

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":

• https://support.mozilla.org/en-US/kb/websites-dont-load-troubleshoot-and-fix-errors
• https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can
• https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites

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You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.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

• 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 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

Thanks very much for your response! Unfortunately I had already tried most of those, and the one which I hadn't tried yet (troubleshoot mode) just confirmed that there is a problem. Would welcome any other suggestions!

Thanks very much for your response! Unfortunately I had already tried most of those, and the one which I hadn't tried yet (troubleshoot mode) just confirmed that there is a problem. Would welcome any other suggestions!

Just to let you know, you're not the only one with this issue. I'm the System admin at my company and I've been experiencing this for the past two to three weeks as has a few of our other users who also prefer Firefox over Chrome, even though we are a Google Workspace shop. I've also tried everything mentioned above, including this solution: https://superuser.com/questions/1280239/firefox-secure-connection-failed-ssl-error-bad-mac-alert

Thanks so much for your response! Really appreciate knowing that it's not just me. I was contemplating reinstalling Firefox since that's the only thing I haven't tried yet. Did you try that?

Please let me know if you find a solution, I'm sure you have a much better chance of figuring this out than I do!

Thanks so much for your response! Really appreciate knowing that it's not just me. I was contemplating reinstalling Firefox since that's the only thing I haven't tried yet. Did you try that? Please let me know if you find a solution, I'm sure you have a much better chance of figuring this out than I do!

I haven't re-installed Firefox, but I did ask a similar question and got a response. Check out the fifth post down from "jscher2000". From my preliminary testing setting the "security.tls.enable_0rtt_data" in "about:config" seems to be working just fine for right now. I'm going to see how Google sites respond to this setting be disabled throughout the day before marking it as having solved my issue.

This could be a problem with the Zero Round Trip Time Resumption (0rtt) feature. You can try to set security.tls.enable_0rtt_data = false on the about:config page to disable this feature until this is fixed by Google or Mozilla to see if that helps.

See also:

• /questions/1376015 Issue with most Google sites on Firefox v100 64bit

scriptguru1701 and cor-el - Thank you both so much! It's working now! Yay! (I was getting so tired of being stuck using Chrome...)