Are you using an ad blocker on the laptop? An adblocker like adguard at the dns level? That seems like a certificates issue. Are you using any particular about:config setting that can be messing with certificates?

Thank you Careca. I'm not using any ad blockers. There is nothing different on the laptop from what I have on my PC. That is what is frustrating.

The Firefox version 128.6.0esr (64-bit), works perfectly on my PC. I had a different version on my laptop. I uninstalled that version, rebooted, then installed version 128.6.0esr (64-bit). Surprisingly, it worked for about a couple of minutes and I had access to a couple of sites, before crashing again.

I can use the other Chrome, Edge and Opera with NO issues. Not sure why Firefox is not working.

Thanks again

What security software are your running? Also try renaming the cert9.db file in your profile folder while Firefox is not running so that a new one is generated.

Could try setting:

security.certerrors.mitm.auto_enable_enterprise_roots security.enterprise_roots.enabled

true

On about:config

Also maybe deleting the profile folder, firefox will create a new one, bookmarks prefs etc all gone of course.

%UserProfile%\AppData\Roaming\Mozilla\Firefox\Profiles

Hi. jonzn4SUSE. Thanks.

Using Ultra AV. Shut that down and now using Windows Security and Firewall. Also renamed cert.db. I am now able to use a couple of sites, but it seems like Firefox is slower in uploading websites than other browsers..

Will keep trying.

Thanks careca. Updated the settings as you recommended. Better performance overall, but some notable delays in loading some websites remains. Have switched to Opera at this point. Will try again with FF at a future point.