Repeatedly, repeatedly, repeatedly get SECURE CONNECTION FAILED - An error occurred during a connection to xxxxxxxx.com. PR_END_OF_FILE_ERROR Error code: PR_END_OF_FILE_ERROR The page you are trying to view cannot be shown because the authenticity of the received data could not be verified. Please contact the website owners to inform them of this problem. There are few attempted web sites that do not get blocked with this message -- EVEN WWW.FIREFOX.COM. I've tried downloading an update to Firefox, but have problems with doing it -- have often gotten the above notice even when trying to download update! Keep getting "Update Failed". Have no trouble accessing any sites using Safari. I'm running a late 2012 21" iMac with macOS Catalina Version 10.15.7